Calculate the weight in g. of 2.5 moles of ethane [C₂H₆]. [C = 12, H = 1]

Calculate the molecular weight of 2.6 g of a gas which occupies 2.24 lits. at 0°C and 760 mm press.

Calculate the number of moles of KClO₃ that will be required to give 6 moles of oxygen.

Calculate the weight of the substance if it's molecular weight is 70 and in the gaseous form occupies 10 lits. at 27°C and 700 mm pressure.