Give a single term substitute for each of the following:

i) 6.023 x 10²³ molecules ii) 22.4 litres of gas at STP

iii) 1/12th part of the mass of one atom of carbon

iv) The half of relative molecular mass

v) Molecular mass / atomic mass

Classify the following based on atomicity:

i) Chlorine ii) Neon

iii) Phosphorous iv) Ozone

Identify and correct the mistake in each of the following:

i) The molar volume of gas at STP is 22.4 cm³.

ii) 2 x R.M.M. = V.D.

iii) An atom cannot exist independently.

iv) The ratio of atoms in a molecule may be integral or simple or may not be fixed.

v) H₂O is a homo atomic molecule.

Modern atomic theory takes up the wave concept, principle of uncertainty and other latest discoveries to give a clear-cut picture about an atom. State the findings of modern atomic theory.

How will you establish the relation between vapour density and molecular mass of a gas by applying Avogadro’s law?