Which of the following is NOT true about gases?

[ace123]

Which of the following is NOT true about
gases?
1. The volume a gas occupies is directly
proportional to its molecular weight.
2. The gas is at STP if it is at 273 K and 1
atm.
3. Gases exert pressure on their surround-
ings.
4. Gases can expand without limit.
5. The density of a gas can be increased by applying increased pressure.

Now I know that 1 is wrong. But I was thinking shouldn't 4 technically be wrong because the gases only expand to fill the container they are in. In other words a gas in bottle can't expand without limit. Is this reasoning correct in any way?

 

[chemisttree]

But I was thinking shouldn't 4 technically be wrong because the gases only expand to fill the container they are in. In other words a gas in bottle can't expand without limit. Is this reasoning correct in any way?

If the system is a closed vessel you are correct. If there is no container, they can expand without limit.

 

[ace123]

Since it didn't state anything about that. So therefore I have an argument?

 

[mgb_phys]

It didn't say there was a container!

 

[ace123]

It didn't say that it wasn't in a container. SO...?

 

[mgb_phys]

Unfortunately there are two sides to physics.
1, Understanding the behaviour of the real world - and what maths to apply where
2, Understanding what exam questions mean.

 

[ace123]

Lol. Good thing chem isn't physics. Therefore exam questions shouldn't be ambiguous.