CBSE - Class 9 Science Atoms and Molecules Worksheet
1.
Calculate the molar mass of the following substances. (a) Ethyne, $C_2H_2$
2.
Calculate the molar mass of the following substances. (b) Sulphur molecule, $S_8$
3.
Calculate the molar mass of the following substances. (d) Hydrochloric acid, HCl
4.
Calculate the molar mass of the following substances. (c) Phosphorus molecule, $P_4$ (Atomic mass of phosphorus = 31)
5.
Calculate the molar mass of the following substances. (e) Nitric acid, $HNO_3$
6.
Write the chemical formulae of the following. (e) Calcium carbonate.
7.
Give the names of the elements present in the following compounds. (a) Quick lime
8.
Give the names of the elements present in the following compounds. (b) Hydrogen bromide
9.
Give the names of the elements present in the following compounds. (c) Baking powder
10.
Write the chemical formulae of the following. (d) Aluminium chloride
11.
Brief about the atomic mass unit?
12.
Write the chemical formulae of the following. (c) Copper nitrate
13.
A 0.24 g sample of compound of oxygen and boron was found by analysis to contain 0.096 g of boron and 0.144 g of oxygen. Calculate the percentage composition of the compound by weight.
14.
Write the chemical formulae of the following. (b) Calcium oxide
15.
When 3.0 g of carbon is burnt in 8.00 g oxygen, 11.00 g of carbon dioxide is produced. What mass of carbon dioxide will be formed when 3.00 g of carbon is burnt in 50.00 g of oxygen? Which law of chemical combination will govern your answer?
16.
Write the chemical formulae of the following. (a) Magnesium chloride
17.
What are polyatomic ions? Give examples.
18.
Give the names of the elements present in the following compounds. (d) Potassium sulphate.
