Question

calculate the number of atoms present in 20g of S8 molecules​

Answer 1

3.76375 x 1022 molecules

Explanation:

The molecular mass of the sulphur molecule is 32 × 8 = 256 u.

1 mole of sulphur molecules is equal to 256 grams.

This means 256 g of solid sulphur contains = 6.022 x 1023 molecules.

Then, 16 g of solid sulphur contains =6.022 x 1023 / 256 = 16 molecules

= 3.76375 x 1022 molecules

Therefore, 16 g of S8 contains 3.76 x 1022 molecules.

Answer 2

0.470 × 10²³  number of molecules  

Explanation:

Given: mass of S₈ = 20 g, molecular weight = 256

We know that,

Molecular weight of any substance has molecules = Avogadro's number

256 g of S₈ = 6.022 × 10²³ molecules

20 g of  S₈  = x number of molecules

x = 6.022 × 10²³ × 20/256

  = 0.470 × 10²³  number of molecules