Question

A gold sample contains 90% of gold and silver the rest is copper. how many atoms of the gold are present in 1 gram of this sample of gold

Answer 1

Relative Atomic Mass of Gold = 197

Meaning 197 g of Gold contains = 6.02 x 10∧23 atoms of Gold (Avogadro's No.)

Mass of gold in the sample = 90% x 1 g = 0.9 g

If 197 g ≡ 6.02 x 10∧23 atoms
∴ 0.9 g ≡ (0.9 x 6.02 x 10∧23) ÷ 197
             ≡ 2.75 x 10∧21 atoms

Answer 2

Answer:

Here is ur answer. ☆☆☆☆