Question

Find the no. of copper atom present in 10gram of 22caret gold. ​

Answer 1

Answer:

There is 2 parts of, out of 24 parts, copper is present.

Answer 2

Answer:

first of all, find the percentage of copper present in 22-carat gold.

Explaination:

percentage of copper in 22 carat gold = (24 - 22)/24 × 100 = 100/12 = 25/3 %

now,

weight of copper in 10g of 22 carat gold = 25/3 % of 10g = 25/3 × 10/100

= 10/12 g

now,

number of copper atoms in (10/12)g = number of mole of copper × Avogadro's number

= given weight/atomic mass × 6.023 × 10²³

= (10/12)/63.5 × 6.023 × 10²³

= (10 × 6.023)/(12 × 63.5) × 10²³

= 0.079 × 10²³

= 7.9 × 10²¹