Question

nickel makes up to 20% of the total mass of coin. The coin has a mass of 10.0g. how many nickel atoms are in the coin?
A- 2.05 x 10^22
B- 4.30 x 10^22
C- 1.03 x 10^23
D- 1.20 x 10^24

Answer 1

Answer:

D 1.20 ×10^24many nickel atoms are in the coin

Answer 2

Answer:

A-2.05x10^22

Explanation:

So 20% of 10g is 2g and there is 2g of nickel present in the coin of mass 10g. next we calculate the moles of nickel present in the coin which would be 2÷59 (59 being the Ar of nickel),  we would get 2/59 which is 0.0341.

now 0.0341 moles are present in the coin, if 1 mole of nickel has 6.02x10^23 atoms in the coin then we would have to multiply 0.0341 with  6.02x10^23 to get the number of atoms present in the coin which would be 0.0341 x 6.02x10^23= 2.05x10^22