CBSE - Class 9 Science Atoms and Molecules Worksheet
1.
Write the chemical formulae of the following. (b) Calcium oxide
2.
Write the chemical formulae of the following. (a) Magnesium chloride
3.
Give the names of the elements present in the following compounds. (b) Hydrogen bromide
4.
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.
5.
Give the names of the elements present in the following compounds. (a) Quick lime
6.
Give the names of the elements present in the following compounds. (c) Baking powder
7.
Write the chemical formulae of the following. (e) Calcium carbonate.
8.
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?
9.
Calculate the molar mass of the following substances. (c) Phosphorus molecule, $P_4$ (Atomic mass of phosphorus = 31)
10.
What are polyatomic ions? Give examples.
11.
Calculate the molar mass of the following substances. (b) Sulphur molecule, $S_8$
12.
Write the chemical formulae of the following. (c) Copper nitrate
13.
Brief about the atomic mass unit?
14.
Calculate the molar mass of the following substances. (a) Ethyne, $C_2H_2$
15.
Write the chemical formulae of the following. (d) Aluminium chloride
16.
Give the names of the elements present in the following compounds. (d) Potassium sulphate.
17.
Calculate the molar mass of the following substances. (d) Hydrochloric acid, HCl
18.
Calculate the molar mass of the following substances. (e) Nitric acid, $HNO_3$
