Hi Jeryl T,
Since you do not know what is your first Chemistry topic in 2013, we shall do some recap on Sec 3 stuff.
Before you proceed further, I want to remind you ( Oh no, Mrs Chew wants to nag again? ) that Chemistry needs to spend some time to memorise the information before you can do A LOT OF questions. 🙂
Every week, I shall try to give you something ( I will not give you a lot each time so dont worry!!) to memorise and I will give you a short worksheet to test your memory+ understanding during class.
I AM VERY SURE , WITH THESE KNOWLEDGE IN YOUR HEAD, YOU CAN DO VERY WELL! I have confidence in you!
For you, this week homework is to STUDY and REMEMBER
– Some common gases’ solubility in water
– Some common gases’ density (relative to air)
– Collection of Gases methods
– Some common drying agents for gas
Some common gases’ solubility in water
- More common gases i.e oxygen, carbon dioxide and hydrogen are nearly insoluble in water.
- More “chim” gases ( those which our young siblings do not know) i.e ammonia, hydrogen chloride and chlorine gases are soluble.
Some common gases’ density (relative to air)
- Hydrogen, Ammonia –> less dense ( you can remember Handsome Admirer Likes Damsel)
- Carbon dioxide, hydrogen chloride and chlorine gas –> More dense ( you can remember CD, Heavy Cat and Cat sinks in water )
- Oxygen –> Equally dense
Collection of Gases methods
- Displacement of air – downwards delivery ( Means gas is collected at the bottom, so it is used when gas is denser than air)
- Displacement of air – upwards delivery ( Means gas is collected at the top, so it is used when gas is less dense than air)
- Displacement of water – used when gas is insoluble in water
Some common drying agents for gas
- Concentrated sulfuric acid ( used for acidic gas)
- Quick lime aka Calcium oxide ( used for alkaline gas i.e ammonia)
- Fused calcium chloride ( used for general gases like hydrogen and oxygen as it is neutral in nature)
I want your commitment to MEMORISE these information hor! 🙂
Watsapp me when you know the topic of Chemistry you are learning at school currently! See ya!