Question

you are given 25g of sodium sulphate. calculate he number of moles of sodium sulphate you have

Answer 1

Answer:

Correct option is

B

12.044×10

23

sodium ions

C

1 mole of Na

2

SO

4

D

6.022×10

23

sulphur atoms

Molecular weight of Na

2

SO

4

=142

Hence, no. of moles in 142 g of Na

2

SO

4

=

142

142

= 1 mole

Number of units ( ions, atoms or molecules) in one mole of a substance = Avogadro's number

In 1 mole of Na

2

SO

4

= 6.022×10

23

sulphur atoms

In 1 mole of Na

2

SO

4

= 2×6.022×10

23

sodium ions