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Question
Solve the following problem:
Find out the molar mass of the following compounds:
Sodium carbonate, decahydrate (Na2CO3.10H2O)
(At. mass: Cu = 63.5; S = 32; O = 16; H = 1; Na = 23; C = 12; Fe = 56; N = 14)
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Solution
Molar mass of Na2CO3.10H2O
= (2 × At. mass Na) + (1 × At. mass C) + (13 × At. mass O) + (20 × At. mass H)
= (2 × 23) + (1 × 12) + (13 × 16) + (20 × 1)
= 46 + 12 + 208 + 20
= 286 g mol–1
Molar mass of Na2CO3.10H2O = 286 g mol–1
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