Calculate the molar mass of the following compounds

CBSE Class 9 CBSE Class 9 Science
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1

Calculate the molar mass of the following compounds.
(i) Lead sulphate
(ii) Calcium phosphate
[Given atomic masses of various elements, Ca = 40 u, S = 32 u, O = 16 u, Pb = 207 u and P = 31 u]

2

(i) Molar mass of lead sulphate ($Pbs{{O}_{4}}$)
= atomic mass of Pb + atomic mass of S + 4 X atomic mass of O
= 207 + 32 + 4 x 16 = 207 + 32 + 64
= 303 u = 303 g/mol
(ii) Molar mass of calcium phosphate
= 3 x atomic mass of Ca + 2 x (atomic mass of P) + 8 X (atomic mass of O)
= 3x40 + 2x31 + 8x16 = 120 + 62 + 128 = 310 u
= 310 g/mol