Atoms and Molecules MCQ/Objective questions Chapter 3 Class 9 Science
7. What is the mass of—(a) 1 mole of nitrogen atoms? (b) 4 moles of aluminium atoms (Atomic mass of aluminium= 27)? (c) 10 moles of sodium sulphite (Na2SO3)?
6. Calculation of atomic masses of molecules (a) Ethyne, C2H2(b) Sulphur molecule, S8(c) Phosphorus molecule, P4 (Atomic mass of phosphorus= 31)(d) Hydrochloric acid, HCl(e) Nitric acid, HNO3.
4. Write the chemical formulae of the following. 5. Give the names of the elements present in the following compounds.