Question

A metal carbonate contains 40% metal. What is the percentage of metal in its hydroxide?​

Answer 1

Answer:

An oxide of a metal (M) contains 40 % by mass of oxygen.

100 g of the oxide will contain 60 g of metal and 40 g of oxygen.

Metal (M) has an atomic mass of 24.

40 g of metal corresponds to

24

60

=2.5mol

Oxygen has an atomic mass of 16.

60 g of oxygen corresponds to

16

40

=2.5mol

Hence, the ratio of the number of moles of metal to oxygen is 1:1.

Answer 2

An oxide of a metal contains 40% by mass of Oxygen.

100g of the oxide will contain 60g of metal and 40 g of Oxygen.

Metal has an atomic mass of 24.

40g of metal corresponds to 60/24 = 2.5 mol.

Oxygen has an atomic mass of 16.

60g of Oxygen corresponds to 40/16 = 2.5 mol.

Hence, the ratio of the number of moles of metal to Oxygen is 1:1.......