Numerical Problems of Chemical Equation

Samples of the gases O₂, N₂, CO₂ and CO under the same conditions of temperature and pressure contain the same number of molecules represented by X. The molecules of Oxygen, occupy V litres and have a mass of 8 g. Under the same conditions of temperature and pressure :
What is the volume occupied by : 3X molecules of CO? [C=12,N=14,O=16]

The equation 4NH₃5O₂ → 4NO + 6H₂O represents the catalytic oxidation of ammonia. If 100 cm³of ammonia is used, calculate the volume of oxygen required to oxidise the ammonia completely.

The ratio between the number of molecules in 2g of hydrogen and 32 g of oxygen is
[Given that H=1,O=16]

The gases chlorine, nitrogen, ammonia and sulphur dioxide are collected under the same conditions of temperature and pressure. The following table gives the volumes of gases collected and the number of molecules (x) in 20 litres of nitrogen. You are to complete the table giving the number of molecules in the other gases in terms of x.

The reaction between 15 g of marble and nitric acid is given by the following equation:

CaCO₃ + 2HNO₃ Ca(NO₃)₂+ H₂O + CO₂

Calculate: the volume of carbon dioxide evolved at S.T.P.

66g of ammounium sulphate is produced by the action of ammonia on sulphuric acid.

Write a balanced equation and calculate:

(a) Mass of ammonia required.

(b) The volume of the gas used at the S.T.P.

(c) The mass of acid required.

What volume of oxygen is required to burn completely a mixture of 22.4 dm³ of methane and 11.2 dm³ of hydrogen into carbon dioxide and steam?

CH₄ + 2O₂ → CO₂ + 2H₂O

2H₂ + O₂ → 2H₂O

Calculate the percent composition of Potassium chlorate KClO₃.