Methane burns in oxygen to form carbon dioxide and water vapour as given by the equation
CH_4(g) + 2O_2(g) ➝ CO_2(g)+ 2H₂O_(g)
Calculate: (i) the volume of oxygen needed to burn completely 50 cm³ of methane and (ii) the volume of carbon dioxide formed in this case.

An atom has 11 protons, 11 electrons and 12 neutrons. What is the atomic number and the name of the element?

State the law of multiple proportions

List the uses of isotopes?

What is isotone? Give an example.

Draw the structure of oxygen and sulphur atoms.

Calculate the number of neutrons, protons and electrons (i) atomic number 3 and mass number 7 (ii) atomic number 92 and mass number 238.

Assign the valency of magnesium and sulphur

Define quantum numbers