Basic Laboratory Orientation

The first time in the school lab was an eye-opener for me. The lab was big and well ventilated and had a wide range of items that were totally alien to me. I learnt about many laboratory apparatus that I had never seen before, such as the pipette and burette. I also learnt about the rules and regulations in the lab and what I must do when an accident occurs.

Here are some examples of what to do when an accident occurs.

1. What should you do if you accidentally spilled some strong acid onto your skin?
Answer: Wash it thoroughly with plenty of water.

2. David poured 30cm^3 of acid into a beaker from a container meant for the entire class. He only used 20cm^3. What should he do with the excess acid?
Answer: He should pour the excess acid into a special bottle meant for disposal as instructed by his teacher. Warning! Do not pour it into the dustbin as it requires special disposal methods and is also dangerous for other lab users.

3. Why is it dangerous to leave a non-luminous flame unattended?
Answer: A non-luminous flame can hardly be seen and may cause others to burn themselves accidentally.

Here is a picture showing you some basic lab apparatus.

 

 

One interesting thing I learnt in the lab is how to light a Bunsen burner.

 

The best way to light a Bunsen burner would be to close the air-hole, turn on the gas tap slowly and ignite a lighter near the mouth of the barrel.

 

Here is the picture of a Bunsen burner with its parts labelled.

Here is a video on how to light a Bunsen burner.

When the air inlet of the Bunsen burner is closed, you get a luminous flame.
When the air inlet of the Bunsen burner is opened, you get a non-luminous flame.

What are the differences between a luminous and non-luminous flame?

Firstly, the flame of the luminous flame is unsteady whereas the flame of the non-luminous flame is steady.

Secondly, the luminous flame can be seen from a distance but the non-luminous flame cannot be seen from a distance.

Thirdly, the luminous flame is not as hot as the non-luminous flame, which means that the non-luminous flame is hotter than the luminous flame.

Why does a "strike-back" occur when the air holes are fully opened?
Answer: When the air-holes are fully opened, a large supply of air enters and the gas burns at the jet instead of the mouth of the barrel, causing a "strike-back".


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