Crystal growing

During the holidays, our Science teacher instructed us to grow sugar crystals for our holiday homework. It was an interesting experiment for me. I'm going to show you the procedures I followed to grow my crystal.

Procedures

1. Put a 3:1 sugar to water ratio into a pan.
2. Heat up the pan and stir the sugar until all of it dissolves and you get a hot solution.
3. Pout the solution into a glass jar or a thermal flask.
4. Tie a string to a wooden chopstick and tie the other end of the string to a seed crystal or a metal clip.
5. Suspend the string into the solution.
6. Keep the glass jar in a place where it will not be disturbed.
7. You should get results in about 1-3 days:D

Here is a video I found on YouTube. You can refer to it if you want to grow sugar crystals.

Thanks for reading!

Personal work samples

In this blog post, I am going to show you some of my work samples. Enjoy!

Worksheet 1

Worksheet 2

This is the Science spelling test in which i got full marks:D

This test will be quite memorable as it is my first test and i got an A1

Worksheet 9

Worksheet 8

Worksheet 7

Worksheet 3

Worksheet 4

Worksheet 5

Worksheet 6

Here are some pictures from > http://benaiahhoong.wix.com/scienceporfolio

Experiment on the boiling point of water

Boiling water

Boiling water picture from above

Chemical experiment with copper sulfate (ll) crystals

Bunsen burner

Thanks for viewing!

Self directed and independent learning

A: Independent Research

Theme 1: Nature of Science

Chapter 1: Introduction to Science and Scientific Method
Topic 1: Interview with Scientist
Imagine that you are given a chance to interview any scientist from the past or present.

• Who would you choose? Give reasons for your choice.

I would choose Isaac Newton. He is widely recognized as one of the most influential scientists of all time and as a key figure in the scientific revolution. Isaac Newton formulated the laws of motion and universal gravitation,which plays a key part in the understanding of Science and dominated the scientists' view of the physical universe for the next 3 centuries.

 Prepare about 4-5 important questions that you would want to ask.

• How did you formulate the laws of motion? 
• What gave you inspiration to persevere, formulate so many laws and study so much, such as the speed of sound? 
• How difficult was it to formulate so many laws? 
• What attitudes should a good scientist show in order to succeed? 

• Now, with the list of questions, imagine yourself to be the scientist you have chosen, how
would you answer those questions.

• One good attitude a scientist should have is perseverance. I persevered and showed true determination, stuck to my beliefs and finally formulated the laws of motion. 
• I was influenced by many other great mathematicians such as Galileo and Copernicus. I was inspired to be even greater than them. I guess it's very important to dream big. 
• It was very difficult. I had to overcome many obstacles on the way. Many people criticized me and believed that everything I wrote about was nonsense. I persevered and proved them wrong. 
• A good scientist must have many good attitudes. A good scientist must be honest, perseverant, inquisitive, brave, open-minded, has a passion for learning and has a desire to improve the human condition. 

Theme 2: Measurements

Chapter 2: Physical Quantities, Units and Measuring Instrument
Topic 2: Measurement units of the past

Since the start of civilization, humans have also asked questions about the world. How far is your
cave, how heavy is a car, how long it takes to travel. Today, 95% of the world uses the metric
system, but this was not always so. A variety of measurement units have been used in the past.
Many of these are easily recognized, however, there are many that are obsolete.
For example, palm, bushel and Troy.

Who: Ancient Egyptians, Ancient Romans and Ancient Hebrews

What: The most widespread unit of measure in the ancient world was the cubit. It was based on the length of the forearm from the elbow to the tip of the middle finger. (17 - 22 in.)

When: Long before 19th Century

Where: Ancient Egypt and Ancient Rome

Why: When humans first started measuring things, they did not have universally accepted artificial measuring devices. They simply used familiar, everyday objects around them to create measuring standards.

reference: http://voices.yahoo.com/how-people-originally-measured-using-familiar-objects-4112461.html

Topic 9: Water in Singapore

Water is a very precious resource on earth. It is important to have reliable water sources to meet
Singapore demand of water. NEWater is highly purified reclaimed water. It is produced from
treated used water that is further purified using advanced membrane technologies such as reverse
osmosis.



reference: https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEifoU9y3Hq6J517GWSp4iUG7n87zjdz7T_RphoVFY_ZxWebuW0I3ji4QrA5ZQ2szOt9iV2aEufepg-ZiaOfNCicdgG07P2X6PncHzaHp6BJL0ol9jjxD0zjJstt9GoREdY34bIcPlV_FK4/s1600/Desalinated+Water.jpg

1. Four National taps in Singapore

1. local catchment water
2. imported water
3. NEWater
4. desalinated water

2.The R.O. water purification method involves forcing water through a semi-permeable membrane, which filters out a select number of water contaminants, depending on the size of the contaminants.

In general, if the contaminants are larger in size than water molecules, those contaminants will be filtered out. If the contaminants are smaller in size, they will remain in the drinking water. Reference: http://www.waterbenefitshealth.com/reverse-osmosis-water.html.


Here is a video on Yotube about reverse osmosis.

Here are some of the benefits of using reverse osmosis to purify water

Pure and clean drinking water
Minimal maintenance
No unwanted odors or tastes
More cost effective than other water purification methods
Convenient

Theme 7: Personal Health

Chapter 7: Respiration and Circulation

Topic 13: Asthma in Singapore

Asthma is an illness that is increasing in frequency worldwide. One reason for this may be
increasing levels of air pollution.

1 and 2. The cause of asthma is poorly understood, but it may be partly inherited.Everyone's lungs are sensitive to different things such as pollen, air pollution, or strong chemicals. In simple terms, people with asthma have lungs that are more sensitive than average.

There are 3 processes in the lungs that produce asthma symptoms. First, the inner linings of the airways become inflamed. They swell up, leaving less room for air to pass through. Second, the muscles around the airways can tighten, closing them further. Finally, the airways produce mucus in response to the inflammation, clogging the shrunken tubes.

Asthma is in part an allergic response. It may be triggered by some external substance that particularly irritates your lungs. These triggers are often small protein particles called allergens. Some people are sensitive to more than one trigger. Common allergens include:
animal dander
cockroach particles
grass, tree, and ragweed pollen
house dust mites
moulds

Other people can get an asthma attack from something they swallow rather than breathe. Examples of these triggers include:
ASA* and other anti-inflammatory medications
nuts or shrimp
preservatives found in some drinks or foods

While most people develop asthma as children, adults can become asthmatic by being exposed to allergens, irritants, or occupational sensitizers for a long time. People who work with the following products may be at increased risk:
antibiotics
cotton and flax
detergents
foams and paints
grains and cereals
insulation and packaging materials

Asthma attacks can also be triggered by non-allergic irritants, such as:
laughing hard, crying, shouting
smog and smoke
strong smells (e.g., paint fumes, perfumes, cleaning products)
suddenly breathing cold air
vigorous exercise
viral infections such as the common cold or the flu
reference: http://bodyandhealth.canada.com/channel_condition_info_details.asp?disease_id=137&channel_id=2014&relation_id=94590

3. It is well understood that air pollutants often act as a trigger to make people’s asthma symptoms worse.

In 1995 the Committee on the Medical Effects of Air Pollution (COMEAP) concluded that ‘exposure to ambient concentrations of air pollutants is associated with an increase in exacerbations of asthma in those who already have the condition’, and more recent evidence has only served to confirm this.

Asthma UK, partners of the Healthy Air Campaign, say this: “Two-thirds of people with asthma tell us that traffic fumes make their asthma worse and 42% find that traffic fumes discourage them from walking or shopping in congested areas. And 85% of people with asthma tell us they are concerned about the effect that increasing vehicle fumes will have on their and their family’s health in the future.”

However, the question of whether air pollution causes asthma is still open for debate. There is some strong evidence to suggest causation. Asthma UK believe that pollution plays a role in causing asthma in children and adults, as well as being a trigger that can make people’s asthma symptoms worse. The Aphekom Study, which took the work of 60 scientists across 12 countries in Europe suggests that living near busy roads could be responsible for some 15-30 percent of all cases of asthma in children.

reference: http://healthyair.org.uk/air-pollution-and-asthma/

4. SMART Automobile rolled out Singapore’s fi rst fl eet of 100 commercially-run Mercedes-Benz CNG-petrol bi-fuel E200 NGT (Natural Gas Technology) taxis in December 2005. These bi-fuel vehicles give SMART drivers the fl exibility to run on petrol should the vehicle run out of CNG. With more environmentally-friendly modes of transport available, the public can also do their part for the environment.Besides CNG vehicles, hybrid vehicles are also increasingly popular. Toyota launched the second generation Prius in Singapore in May 2006, while the second generation Honda Civic Hybrid was launched in June 2006. Powered by a combination of petrol and electricity, hybrid cars generally consume about half the average amount of petrol compared to their conventional equivalent and emit less air pollutants. Hybrid cars have also proven that they perform well under city-driving conditions and can double the mileage attained. For example, the Toyota Prius can achieve as much as 23km per litre of petrol compared to between 10 to 12km per litre for an equivalent conventional car. As at end 2007, there were about 1,062 hybrid vehicles on our roads, which include those under the car-sharing scheme operated by Honda Diracc. With more hybrid models becoming available, car owners will be able to take advantage of the Green Vehicle Rebate to reduce their impact on the environment.

Our land transport system plays a critical role in facilitating economic development and enhancing Singapore’s attractiveness as a place to live and work. An efficient land transport system that provides good linkages to our air and seaports is crucial to firmly anchor Singapore’s economy with the rest of the world. As a small and dense city state, choosing public transport as the choice mode for day-to-day commuting ensures our city’s liveability and high quality of life. Over the next 10 to 15 years, the Ministry of Transport (MOT) aims to increase the current public transport modal share of 63% to at least 70%, so as to achieve a high quality and sustainable land transport system that is able to handle a significantly larger population base. This target, if achieved, will help ensure that Singaporeans continue to enjoy a high quality urban living environment.

However, patients with medical problems like asthma, chronic lung disease, chronic sinusitis and allergic skin conditions may experience more severe symptoms. Children and the elderly in general, may also be more likely affected. NEA closely monitors the haze situation. During severe haze conditions, the public is kept informed of the PSI at three-hourly intervals. Health authorities will also alert Singaporeans on preventive measures to take at such times. State of the Environment 2008 Report Singapore Chapter 1 p24 On the international front, Singapore has been working closely with the Indonesian local authorities as well as relevant ASEAN countries to tackle the trans-boundary smoke haze. NEA assists the Indonesian authorities in their fire-fighting efforts by providing satellite pictures of hotspots to help them locate the fires on the ground. At the 10th ASEAN Ministerial Meeting on the Environment (AMME) held in the Philippines in November 2006, Singapore pledged US$50,000 to the ASEAN Haze Fund. In addition, Singapore accepted Indonesia’s invitation to collaborate with the Muaro-Jambi Regency to enhance its capacity to deal with land and forest fires.As the custodian of air quality in Singapore, NEA will sustain its initiatives and strategies to safeguard air quality. What inspires and spurs us on is our desire to ensure that generations to come will continue to enjoy clear blue skies with clean and fresh air.

Reference: http://app.mewr.gov.sg/data/imgcont/1233/016-025%20Air.pdf

B: Critical Reviews

Controlling body movement with light

Neuroscientists report that they can inhibit muscle contractions by shining light on spinal cord neurons. The main question is: How is light able to control body movements?

Neuroscientists have shown that they can control body movements by applying optogenetics to the spinal cords of animals that are awake and alert. They have done this experiment on mice. A light-sensitive protein that promotes neural activity was inserted into a subset of spiral neurons. Light was shone on the mice and their hind legs became reversely immobilized. Results have roved that they were right.

I believe that this article is an eye-opener for many. The findings offer a new approach to studying the complex spinal circuits that coordinate movements and sensor processing. This article really makes me reflect on the wonders of Science. If humans eat the light-sensitive protein and light is shone on them, will the results still be the same? Will our legs become immobilized? Nobody has tested it on humans so I'm not sure if the results will still be the same. All we know is that Science will be taking us on a roller-coaster ride.

Article: http://www.sciencedaily.com/releases/2014/06/140626122047.htm

Early life stress can leave lasting impacts on the brain.

The University of Wisconsin-Madison ave shown that for children, little bits of stress can last a long way, impacting the child's development. The question is: How does early-life stress affect a child?

A team of researchers from the University of Wisconsin-Madison have shown that early-life stress, such as poverty, physical abuse and neglect can change parts of a developing child's brain responsible for learning, memory and the processing of stress and emotion. Different forms of stress can impact different parts pf the brain.

Personally, I believe the researchers are right. Children under a lot of stress have gone suicidal, and some even going crazy. I had experienced stress before during the PSLE. As a result, I had problems trying to sleep and easily got tired in class. Stress can also be health hazards when we get short-term memory loss. This article should serve as a deterrent to parents and I believe that parents would be more careful of their child after reading this article.

Article: http://www.sciencedaily.com/releases/2014/06/140627133107.htm
Thank you for reading!

Reflections on Science performances and experiences

Termly Science Performance
My target is to get A1 for all my Science exams.

My plan to achieve target
1. I have to listen attentively in class
2. Be an inquisitive learner
3. Ask when in doubt
4. Revise consistently
5. Persevere to ace the subject

Improvements
1. I need to read and understand the question better before understanding. To do this, I will analyse the question carefully before answering to prevent any careless loss of marks.

2. I need to understand and revise the topics more consistently and thoroughly before the exams so I will have an ease of mind when answering as I had already revised it before.

3. I need to use key words when answering the questions to prevent careless loss of marks. When answering in the common test, I did not use key words thus losing marks although I knew the answer. I will try memorizing key words found in my notes so that I can ace my tests.

Reflection on Science experiences

Name of activity: Basic lab orientation
Venue: Science lab

reference: http://images.fineartamerica.com/images-medium-large/1-bunsen-burner-flame-.jpg

reference: http://www.scienceprofonline.com/images/science-image-library/microbiology/equipment/bunsen-burner-adjusting-flame-SIL.jpg

 reference:http://joashpoh.files.wordpress.com/2014/01/img_0063.jpg

What I have learnt from the activity

I learnt how to properly use a bunsen burner and how to change the flame from luminous to non-luminous and back. I learnt about the different lab equipments such as the burette and pipette and what their used for. I also learnt what to do when a "strike-back" occurs when lighting a bunsen burner. I think this activity was an eye-opener for me as this is my first time in the school lab, which is spacious and well-ventilated.

What do you like most and least about the activity?

I liked the fact that we were able to turn on the bunsen burner ourselves and observe how the flames turn from luminous to non-luminous.

I disliked memorizing the different lab equipments as there is a wide range of equipments.

What do you learn about your partner from the activity?

I learnt that my partner, Enoch, is actually a person who can project a calm demeanor when faced with adversity. We were unable to light the bunsen burner for the first few times and i was very anxious as most of my classmates have already done so. However, my partner was calm and we finally managed to light the bunsen burner.

Reflections on Science experiments

Name of activity: Making observations

Venue: Science lab

references: http://jonathonscienceblog1i3.wordpress.com/

What I have learnt from the activity

I learnt about the differences between an inference and an observation. I also learnt that when I have to make a lot of observations, it is really helpful to organize them into a table or graph for further manipulation. I learnt a lot of new terms from our Science teacher Mr Tan such as effervescence. I also learnt about the difference between mean, mode and median.

What do you like most and least about the activity?

I like observing the chemical reactions between sodium carbonate and vinegar as it was really cool to see the effervescence of the gas and the sodium carbonate dissolving.

I disliked dripping the methylated spirit on my hand as it felt cool and awkward. I did not like the feeling of it.

What did you learnt about your partner from the activity?

I realized that my partner, Enoch, is really fun and engaging. He helped me a lot with the experiments such as pouring the vinegar to a depth of 1cm, which was really hard.

Reflections on Science experiments

Name of activity: Boiling Point of water

Venue: Science lab

   

reference: http://benaiahhoong.wix.com/scienceporfolio

What I have learnt from the activity

I learnt that we should read the readings of the thermometer at eye level to prevent parallax error. I also learnt about what to do if I accidentally break the thermometer a it is hazardous and poisonous. 

What I liked and disliked about the activity

I liked watching the temperature of the thermometer rising as I found it intriguing. I could also try to plot a temperature over time graph on the thermometer.

I disliked handling the thermometer as there is mercury inside and I am afraid of breaking it.

Thank you for reading!

Issues in teaching and learning Science

Problems I faced in the learning of Science

1. I could not tell the difference between a Scientific law and a Scientific theory. To overcome this problem, I did some online research and finally understood the difference.

Scientific Law: This is a statement of fact meant to explain, in concise terms, an action or set of actions. It is generally accepted to be true and universal, and can sometimes be expressed in terms of a mathematical equation. They explain what will occur in a given circumstance.

Scientific Theory: A theory is an explanation of a set of related observations or events based upon proven hypotheses and verified multiple times by detached groups of researchers. They explain facts and, sometimes, laws.

A law governs a single action, whereas a theory explains an entire group of related phenomena.

2. I had problems with units conversion and faced difficulties in the term 2 class quiz on physical quantities. To overcome this problem, I tried worksheets on unit conversion but still had doubts on my abilities. I am still facing this problem today but I will try my very best to ace units conversion.
Here is a video found on Youtube demonstrating how to convert units easily.

 

Scientific concepts I have learnt

 

1. Organisation

2. Structure and function

3. Systems

4. Cause and effect

5. Attitudes

 

How are these knowledge and skills useful and relevant to the real world?

 

As a student, organisation is really important as I have a lot of notes. If I do not organise my notes properly, I might not be able to find it at a crucial moment such as when I need it to revise for my exams. I need to have the attitude of being meticulous so I can refer to my notes easily. I should also have the attitude of integrity by not copying my friends work. The knowledge of structure and function helps me as when my friend has a bone fracture, I will understand which part of his body is not functioning properly due to the fracture and how I can help him. Understanding systems also help me understand simplest of things such as the heat change of boiling water when ice is submerged in it.

 

What I have learnt which is beyond my textbook/notes knowledge?

1. I found out that there are 5 states of matter, 2 more than the 3 I know of. The 5 states are gaseous, liquid, solid, plasma and Bose-Einstein condensate. These further piqued my curiosity in Science and I went on to find out its structure. (Kinetic Particle Theory)

 

2. I learnt that clocks from the olden days use the concept of pendulums to tell time as the pendulum never stops swinging, so it will be able to tell time correctly. Most watches we use now use batteries and it might slow down in the future.

 

3. I learnt that the phones now are able to store 64 Giga bytes of data, some even more! That's 10^9! All that data is stored in a tiny microchip that will be inserted into the phone. This made me more interested in prefixes.

 

Fun videos:D

To watch more videos, simply click here > AsapSCIENCE

Thank you for reading! 

 

 

 



 





Solutions,suspensions and solubility

Solution
A solution is a homogeneous mixture.

• The particles of solute in solution cannot be seen by naked eye.
• The solution does not allow beam of light to scatter.
• A solution is stable.
• The solute from the solution cannot be separated by filtration (or mechanically).

Suspension

A suspension is a heterogeneous mixture.

• A particles of solute in suspension can be seen by the naked eye.
• The suspension does not allow beam of light to scatter.
• The solute from the suspension can be separated by filtration.

Solubility

The solubility of a substance is the maximum amount of that substance that will dissolve in 100g of solute at a given temperature.

References from Wikipedia 

Separation Techniques

How do you separate a liquid from a soluble solid?
How are you going to separate a liquid from an insoluble solid?
Today's blog post is about separation techniques.

Filtration
This method is used to separate a suspension into its components - the liquid and the insoluble solid. The use of the filter allows the filtrate (liquid) to pass through and retains the insoluble solid particles (residue).

Crystallisation

This method is used to separate a solution into its components - the liquid and the solute (dissolved solid). The solute is obtained in the form of pure crystals. Crystallisation can either be carried out through the rapid cooling of a saturated solution or the slow evaporation of a solution at room temperature. 

Sublimation

This method refers to the direct state change of solid to gaseous state without passing through the liquid state. This method is used to separate a mixture of solids, one of which sublimes. It may be used to obtain a pure sample of the solid which sublimes.

Magnetic separation

This method is used to separate a magnetic material from a mixture containing other non-magnetic materials. A strong magnet is held near the mixture, allowing it to attract magnetic substances while leaving a residue of non-magnetic materials.

Distillation

This method is for the separation and purification of liquids based on the differences in boiling points or volatility of the liquids.

The two main methods of distillation are:

Simple distillation, which is used to separate a pure liquid (solvent) from a solution containing dissolved solids.

Fractional distillation, which is used to separate mixtures of miscible liquids, which have widely different boiling points.

Separating funnel

This method is used to separate immiscible liquids.

Chromatography

This method is used to separate and identify small amounts of substances that are dissolved in solvents, to to determine if a sample is pure.

Thank you for watching. Videos from youtube and pictures from google.

Kinetic Particle Theory, Brownian motion and Diffusion + Inertia

The kinetic model of matter states that all matter is made up of a large number of tiny particles called atoms or molecules that are in continuous random motion.
States of matter (using the kinetic model of matter )

Solid
Arrangement of particles > Closely packed in an orderly arrangement
Motion of particles > Vibrate about fixed positions
Space between particles > Very little
Forces between particles > Very strong attractive forces

Liquid
Arrangement of particles > Loosely packed in an disordered arrangement
Motion of particles > Slip, slide and roll about one another
Space between particles > Little
Forces between particles > Strong attractive particles

Gas
Arrangement of particles > Very far apart in a random arrangement
Motion of particles > Move freely and randomly at high speeds in all directions
Space between particles > Very large
Forces between particles > Weak and negligible attractive forces

Brownian motion

Brownian motion is the random motion of particles suspended in a fluid (a liquid or a gas) resulting from their collision with the quick atoms or molecules in the gas or liquid.

The Roman Lucretius's scientific poem "On the Nature of Things" (c. 60 BC) has a remarkable description of Brownian motion of dust particles. He uses this as a proof of the existence of atoms:

"Observe what happens when sunbeams are admitted into a building and shed light on its shadowy places. You will see a multitude of tiny particles mingling in a multitude of ways... their dancing is an actual indication of underlying movements of matter that are hidden from our sight... It originates with the atoms which move of themselves [i.e., spontaneously]. Then those small compound bodies that are least removed from the impetus of the atoms are set in motion by the impact of their invisible blows and in turn cannon against slightly larger bodies. So the movement mounts up from the atoms and gradually emerges to the level of our senses, so that those bodies are in motion that we see in sunbeams, moved by blows that remain invisible."

To find out more about the Brownian motion, click here
Here is a stimulation of the Brownian motion i found on Google.

Diffusion
Diffusion is the net movement of a substance (e.g., an atom, ion or molecule) from a region of high concentration to a region of low concentration. This is also referred to as the movement of a substance down a concentration gradient. A gradient is the change in the value of a quantity (e.g., concentration, pressure, temperature) with the change in another variable (e.g., distance). For example, a change in concentration over a distance is called a concentration gradient, a change in pressure over a distance is called a pressure gradient, and a change in temperature over a distance is a called a temperature gradient. 
To find out more on diffusion, click here
Here is a picture of Diffusion i found on Google

Inertia

Inertia is the resistance of any physical object to any change in its state of motion, including changes to its speed and direction. It is the tendency of objects to keep moving in a straight line at constant velocity. The principle of inertia is one of the fundamental principles of classical physics that are used to describe the motion of objects and how they are affected by applied forces. Inertia comes from the Latin word, iners, meaning idle, sluggish. Inertia is one of the primary manifestations of mass, which is a quantitative property of physical systems.Isaac Newton defined inertia as his first law in his Philosophiæ Naturalis Principia Mathematica, which states:

The vis insita, or innate force of matter, is a power of resisting by which every body, as much as in it lies, endeavours to preserve its present state, whether it be of rest or of moving uniformly forward in a straight line.

In common usage the term "inertia" may refer to an object's "amount of resistance to change in velocity" (which is quantified by its mass), or sometimes to its momentum, depending on the context. The term "inertia" is more properly understood as shorthand for "the principle of inertia" as described by Newton in his First Law of Motion: that an object not subject to any net external force moves at a constant velocity. Thus, an object will continue moving at its current velocity until some force causes its speed or direction to change.

On the surface of the Earth inertia is often masked by the effects of friction and air resistance, both of which tend to decrease the speed of moving objects (commonly to the point of rest), and gravity. This misled classical theorists such as Aristotle, who believed that objects would move only as long as force was applied to them.

To find out more on inertia, click here

Here is a video on Youtube about inertia. Enjoy!

Thank you for reading!

Classification of matter

Matter exist in 3 physical states: Solid, liquid and gas. However, did you know that matter can exist in 2 other physical states? Incredible! This 2 states are Plasma and Bose-Einstein Condensate.

Plasma

Plasma is loosely described as an electrically neutral medium of positive and negative particles (i.e. the overall charge of a plasma is roughly zero). It is important to note that although they are unbound, these particles are not ‘free’. When the charges move they generate electrical currents with magnetic fields, and as a result, they are affected by each other’s fields. This governs their collective behavior with many degrees of freedom.

Plasma is one of the four fundamental states of matter (the others being solid, liquid, and gas). When air or gas is ionized, plasma forms with similar conductive properties to that of metals. Plasma is the most abundant form of matter in the Universe, because most stars are in a plasma state.

Plasma comprises the major state of matter of the Sun. Heating a gas may ionize its molecules or atoms (reducing or increasing the number of electrons in them), thus turning it into a plasma, which contains charged particles: positive ions and negative electrons or ions. Ionization can be induced by other means, such as strong electromagnetic field applied with a laser or microwave generator, and is accompanied by the dissociation of molecular bonds, if present. Plasma can also be created by the application of an electric field on a gas, where the underlying process is the Townsend avalanche.

The presence of a non-negligible number of charge carriers makes the plasma electrically conductive so that it responds strongly to electromagnetic fields. Plasma, therefore, has properties quite unlike those of solids, liquids, or gases and is considered a distinct state of matter. Like gas, plasma does not have a definite shape or a definite volume unless enclosed in a container; unlike gas, under the influence of a magnetic field, it may form structures such as filaments, beams and double layers. Some common plasmas are found in stars and neon signs. In the universe, plasma is the most common state of matter for ordinary matter, most of which is in the rarefied intergalactic plasma (particularly intracluster medium) and in stars. Much of the understanding of plasmas has come from the pursuit of controlled nuclear fusion and fusion power, for which plasma physics provides the scientific basis.

Click here to find out more about Plasma.

Here is a video found on Youtube about plasma.

Bose-Einstein Condensate

A Bose–Einstein condensate (BEC) is a state of matter of a dilute gas of bosons cooled to temperatures very close to absolute zero (that is, very near 0 K or −273.15 °C^[1]). Under such conditions, a large fraction of the bosons occupy the lowest quantum state, at which point quantum effects become apparent on a macroscopic scale. These effects are called macroscopic quantum phenomena.

Click here to find out more about the Bose-Einstein Condensate

Here is a video on Youtube about the Bose-Einstein Condensate

Thank you for reading! I hope your mind was blown!

Elements, Compounds and Mixtures

Elements, compounds and mixtures are some categories that refer to the composition of a substance. The properties of substances allow scientists to identify a given substance as an element, compound or mixture.

Elements
An element is a substance that cannot be further broken down using chemical reactions to give simpler substances. For example, when common salt is heated and then electrically decomposed, it gives sodium and chlorine which cannot be further broken down into simpler substances. Hence, common salt is a compound while sodium and chlorine are elements.
An element has both a name and a symbol for it to be represented in the periodic table. For instance, an element may be named "hydrogen" and designated the symbol "H".
Here is the picture of a periodic table and a song from AsapSCIENCE. Enjoy!





 

 

An element is either made up of atoms or molecules. A molecule is a group of two or more atoms chemically joined together.

 

So, how do you classify elements?

 

1. Classification by state.

Elements can be classified according to their physical state at room temperature and pressure.

2. Classification as metals/metalloids/non-metals

Elements can also be classified by their metallic properties. Elements that are good conductors of electricity would be classified under metals while elements that are poor conductors of electricity would be classified under non-metals. However, there are some elements that have both metallic and non-metallic properties, which are classified under metalloids.

3. Periodic table classification

Elements belonging to the same column, or group, (vertical) have similar chemical properties while elements in the same row, or period, (horizontal) show a gradual decrease in non-metallic properties.

 

Compounds

A compound is a substance containing 2 or more elements chemically joined together. It can be decomposed to give 2 or more simpler substances. A compound is formed through chemical reaction between different elements. Usually, compounds can be broken back down into their constituent elements by using electricity or heat.

 

Mixtures

A mixture comprises 2 or more substances that are not bonded together through chemical means. It can comprise of elements, compounds or both, and these may be solids, liquids or gases.

 

Differences between a compound and a mixture

1. A compound's melting and boiling points are fixed, while a mixture melts and boils over different temperatures.

2. A compound requires chemical reactions to be separated into its constituent elements while a mixture may be easily separated into its components using physical means.

 

Periodic table

The periodic table is a tabular arrangement of the chemical elements, organized on the basis of their atomic numbers, electron configurations (electron shell model), and recurring chemical properties. Elements are presented in order of increasing atomic number (the number of protons in the nucleus). The standard form of the table consists of a grid of elements laid out in 18 columns and 7 rows, with a double row of elements below that. The table can also be deconstructed into four rectangular blocks: the s-block to the left, the p-block to the right, the d-block in the middle, and the f-block below that.
The rows of the table are called periods; the columns are called groups, with some of these having names such as halogens or noble gases. Since, by definition, a periodic table incorporates recurring trends, any such table can be used to derive relationships between the properties of the elements and predict the properties of new, yet to be discovered or synthesized, elements. As a result, a periodic table—whether in the standard form or some other variant—provides a useful framework for analyzing chemical behavior, and such tables are widely used in chemistry and other sciences.
In the standard periodic table, the elements are listed in order of increasing atomic number (the number of protons in the nucleus of an atom). A new row (period) is started when a new electron shell has its first electron. Columns (groups) are determined by the electron configuration of the atom; elements with the same number of electrons in a particular subshell fall into the same columns (e.g. oxygen and selenium are in the same column because they both have four electrons in the outermost p-subshell). Elements with similar chemical properties generally fall into the same group in the periodic table, although in the f-block, and to some respect in the d-block, the elements in the same period tend to have similar properties, as well. Thus, it is relatively easy to predict the chemical properties of an element if one knows the properties of the elements around it.

The information above is found on Wikipedia

Thank you for reading! The videos above are found on Youtube.

Mass, Weight and Density

Today's blog post is on mass, weight and density. Do not be fooled! Mass is not weight!

MASS
The mass of an object is a fundamental property of the object; a numerical measure of its inertia; a fundamental measure of the amount of matter in the object. Definitions of mass often seem circular because it is such a fundamental quantity that it is hard to define in terms of something else. All mechanical quantities can be defined in terms of mass, length, and time. The usual symbol for mass is m and its SI unit is the kilogram. While the mass is normally considered to be an unchanging property of an object, at speeds approaching the speed of light one must consider the increase in the relativistic mass.
The weight of an object is the force of gravity on the object and may be defined as the mass times the acceleration of gravity, w = mg. Since the weight is a force, its SI unit is the newton. Density is mass/volume.

 

WEIGHT

The weight of an object is defined as the force of gravity on the object and may be calculated as the mass times the acceleration of gravity, w = mg. Since the weight is a force, its SI unit is the newton.For an object in free fall, so that gravity is the only force acting on it, then the expression for weight follows from Newton's second law.
You might well ask, as many do, "Why do you multiply the mass times the freefall acceleration of gravity when the mass is sitting at rest on the table?". The value of g allows you to determine the net gravity force if it were in freefall, and that net gravity force is the weight. Another approach is to consider "g" to be the measure of the intensity of the gravity field in Newtons/kg at your location. You can view the weight as a measure of the mass in kg times the intensity of the gravity field, 9.8 Newtons/kg under standard conditions.
Data can be entered into any of the boxes below. Then click outside the box to update the other quantities.
At the Earth's surface, where g=9.8 m/s² :

The weight of mass kg is Newtons
The weight of mass slugs is pounds

All the information above can be found here>HyperPhysics

DENSITY
The density, or more precisely, the volumetric mass density, of a substance is its mass per unit volume. The symbol most often used for density is ρ (the lower case Greek letter rho). Mathematically, density is defined as mass divided by volume:

If you want to find the volume of something, just divide mass by the density of it.
If you want to find the mass of an object, just multiply its volume by its density.

Thank you for reading! References from Wikipedia.

Here is an interesting video from AsapSCIENCE

Measurements

Imagine trying to measure the inner diameter of a circular cylinder. How are you going to do that? Put a ruler in between? That would not be feasible as a ruler would not be able to fit in. What if we want to measure something that rulers are not able to measure? What do we do? Today's blog post is about measurements and I am going to show you 2 wonderful apparatus for measurements. They are the Vernier Caliper and the Micrometer Screw Gauge.

Firstly, let me talk about the Vernier Caliper.
"The main use of the vernier caliper is to measure the internal and the external diameters of an object." Here is a picture of a Vernier Caliper.

 

Here are the parts of the Vernier Caliper and their functions.

 

1. Outer Jaws: For measuring the external diameter of objects.

2. Inner Jaws: For measuring the internal diameter of objects.

3. Vernier Scale: "A vernier scale is a device that lets the user measure more precisely than could be done by reading a uniformly-divided straight or circular measurement scale. It is scale that indicates where the measurement lies in between two of the marks on the main scale."

4. Depth Probe: To measure the depths of objects.

 

Here is a video on how to use the Vernier Caliper.

 

 

How a Vernier Scale works.

 

 

"The vernier scale is constructed so that it is spaced at a constant fraction of the fixed main scale. So for a decimal measuring device each mark on the vernier is spaced nine tenths of those on the main scale. If you put the two scales together with zero points aligned, the first mark on the vernier scale is one tenth short of the first main scale mark, the second two tenths short, and so on up to the ninth mark—which is misaligned by nine tenths. Only when a full ten marks are counted is there alignment, because the tenth mark is ten tenths—a whole main scale unit short, and therefore aligns with the ninth mark on the main scale."

 

 

A typical Vernier Caliper can measure 0.1mm readings and has a typical maximum accuracy of  +0.05mm.

 

 

Now I will be introducing you to a far more complex instrument that has a maximum accuracy of +0.005mm! It is the Micrometer Screw Gauge.

 

"A micrometer, sometimes known as a micrometer screw gauge, is a device incorporating a calibrated screw widely used for precise measurement of components in mechanical engineering and machining as well as most mechanical trades, along with other metrological instruments such as dial, vernier, and digital calipers. Micrometers are usually, but not always, in the form of calipers (opposing ends joined by a frame), which is why micrometer caliper is another common name. The spindle is a very accurately machined screw and the object to be measured is placed between the spindle and the anvil. The spindle is moved by turning the ratchet knob or thimble until the object to be measured is lightly touched by both the spindle and the anvil."

 

Here are 2 pictures of the Micrometer Screw Gauge.

 



Here is a video on how to use the Micrometer Screw Gauge. Enjoy!

 

Here are the parts of the Micrometer Screw Gauge as found on Wikipedia.

 

Frame

The C-shaped body that holds the anvil and barrel in constant relation to each other. It is thick because it needs to minimize flexion, expansion, and contraction, which would distort the measurement.
The frame is heavy and consequently has a high thermal mass, to prevent substantial heating up by the holding hand/fingers. It is often covered by insulating plastic plates which further reduce heat transference.
Explanation: if you hold the frame long enough so that it heats up by 10°C, then the increase in length of any 10 cm linear piece of steel is of magnitude 1/100 mm. For micrometers this is their typical accuracy range.
Micrometers typically have a specified temperature at which the measurement is correct (often 20°C [68°F], which is generally considered "room temperature" in a room with HVAC). Toolrooms are generally kept at 20°C [68°F].

Anvil

The shiny part that the spindle moves toward, and that the sample rests against.

Sleeve / barrel / stock

The stationary round part with the linear scale on it. Sometimes vernier markings.

Lock nut / lock-ring / thimble lock

The knurled part (or lever) that one can tighten to hold the spindle stationary, such as when momentarily holding a measurement.

Screw

(not seen) The heart of the micrometer, as explained under "Operating principles". It is inside the barrel. (No wonder that the usual name for the device in German is Messschraube, literally "measuring screw".)

Spindle

The shiny cylindrical part that the thimble causes to move toward the anvil.

Thimble

The part that one's thumb turns. Graduated markings.

Ratchet stop

(not shown in illustration) Device on end of handle that limits applied pressure by slipping at a calibrated torque.

 

As you can see, it is actually quite easy to use this measuring instruments.

 

Now I will be introducing a problem when handling this instruments- Zero Error.

I will start off with Zero Error for the Micrometer Screw Gauge. Here is a picture.

As you can see, when there is no zero error, the zeros on the scales align perfectly. However, Positive zero error occurs when the ‘0’ marking of the thimble scale is below the horizontal reference line of the main scale. Negative zero error occurs when the ‘0’ marking of the thimble scale is below the horizontal reference line of the main scale. When zero errors occur, our results will not be accurate. So how do we solve this problem? It's very simple!

Positive zero error
The error is +x mm. To correct the reading, we subtract the error from the measurement.
Negative zero error
The error is -(0.1-y) mm. To correct the reading, we subtract the error from the measurement.

Now I will continue with zero errors for the vernier caliper.



 

"In a vernier caliper, you can either have a positive zero error or a negative zero error if the zero of the main scale does not coincide with the zero of the vernier scale. If the zero mark is slightly on the right side of the zero on the vernier we have a positive zero error. If it is on the left, then a negative zero error. To get the correct reading, the poistive zero error is subtracted from the final reading and the negative Z.E is added."

 

 

Thank you for reading. References from Google, Wikipedia and Youtube.