How many molecules of lithium carbonate are there in 8.62 g of the compound?

Question

a) 74 molecules

b) 647 molecules

c) 0.12 molecules

d) 7.02x10^22 molecules

e) 1.42x10^-23 molecules

Answer 1

8.62 g Li2CO3 = how many moles.
mols = grama/molar mass
grams = 8.62
molar mass = 2*Li + C + 3*16 = 2*6.94 + 12.01 + 3*16 = 73.9
8.69/73.9 = 0.117 mols.
There are 6.02E23 molecules in 1 mol so......