Question

calculate number of moles in 10g of sodium sulphate. Given atomic mass of sodium 23 , sulphur 32 and oxygen 16​

Answer 1

Explanation:

Mass of 1 mole of Na2SO3 = 23 x 2 + 32 + 16 x 3 = 126 g Mass of 10 moles of Na2SO3 = 10 x 126 = 1260 g

Answer 2

Answer:

The number of moles in 10 g of sodium sulfate is 0.070 moles.

Explanation:

We know that the molecular formula of sodium sulfate is $Na_{2} SO_{4}$

Here the molecule contains 2 atoms of sodium, one atom of sulfur, and four atoms of oxygen.

Therefore the molecular mass of sodium sulfate = (2×23)+32+(4×16)

                                                                                = 142 g/mol

The given weight of sodium sulfate = 10 g

so, the number of moles of sodium sulfate = given mass ÷ molecular mass

                                                                       = $\frac{10}{142} = 0.070 moles$