Chemistry Past Questions and Answers

25cm³ of a gas X contains Z molecules at 15^oC and 75 mmHg. How many molecules will 25 cm³ of another gas Y contain at the same temperature and pressure?

25cm³ of a gas X contains Z molecules at 15^oC and 75 mmHg. How many molecules will 25 cm³ of another gas Y contain at the same temperature and pressure?

25cm³ of a gas X contains Z molecules at 15^oC and 75 mmHg. How many molecules will 25 cm³ of another gas Y contain at the same temperature and pressure?

What mass of water is produced when 8.0g of hydrogen reacts with excess oxygen?
[H = 1, O = 16]

A particle that contains 9 protons, 10 neutrons and 10 electrons is a