Question

Obtain the chemical formula of
(i) Potassium dichromate [1]
(ii) Calcium carbonate [1]
(iii) Aluminium sulphate

Answer 1

Answer:

Potassium dichromate - K2Cr2O7

Calcium carbonate - Ca2CO3

Aluminium sulphate - Al2(SO4)3

Answer 2

Obtain the chemical formula of

(i) Potassium dichromate =K2 [Cr2O7]

step:

The valency of potassium (K) is 1+. The valency of dichromate (Cr2O7) is 2+.

Therefore, the chemical formula of potassium dichromate is K2Cr2O7 .

ii) Calcium carbonate = CaCO3

step:

Formula and structure: The calcium carbonate chemical formula is CaCO3 and its molar mass is 100.0869 g mol-1. The molecule is formed by the calcium cation Ca+2 and the carbonate anion CO3-2.

iii) Aluminium sulphate= Al2(SO4)3

I don't know the step for aluminium sulphate.