Calculate the number of atoms in each of the following.

Question

A)1.50g potassium
B)0.470g of oxygen
C)0.555g of silver chlorate,AgCIO3
D)7.57 of platinum

please help i do not understand this

Answer 1

Determine moles, then remember that 1 mol contains 6.022E23 atoms/molecules.
A. 1.50 g K
moles K = 1.50/39.1 = 0.0384
1 mole contains 6.022E23 atoms; therefore, 0.0384 moles will contain 0.0384*6.022E23 atoms = ??

0.470 g oxygen
moles = 0.470/32 = 0.0147
#molecules = 0.0147*6.022E23 = ??
Since oxygen is diatomic (O2), it will contain 2x that for the number of atoms.