Question

Determine the number of H2O molecules in 68.0g of H2O

Answer 1

molecular mass of H2o is 18 g/mol

no. of moles = given mass / molecular mass

= 68÷18

= 3.77 moles

1 mole contains 6.022 *10^23 molecules

then, 3.77 moles contains

= 6.022*10^23 * 3.77

=22.702 * 10^23 molecules

.

.

.

.

.

hope it helps u dear....

keep smiling :)

have a good day....