- 10

- 0

**Question 1:**5L of nitrogen at 100kPa and 298K and 5L of oxygen at 200kPa are pumped into a evacuated 50L cylinder. Temperature remains constant, what is the total pressure in the cylinder?

**Correct Answer:**30kPa

**My answer:**300 kPa

**Question 2**: A 10L flask containing nitrogen at 500mmHg is connected via a closed tap to a 4L flask containing oxygen at 800mmHg pressure, if the tap is opened what will be the final pressure assuming temperature remains constant?

**Answer:**586mmHg

**My answer:**1300mmHg

**Formulas I used:**

pV = nRT (to find mols)

PA = (nA/nA+nB) x PT

How did they get these answers...cos I can't seem to get them..?? Any help would be appreciated...