Answer:
The correct answer is B) 3 x 1021 molecules
Explanation:
We use Avogadro's number (in one mole of compound there are 6, 02x10e23 molecules) and calculate the weight of one mole of water:
Weight 1 mol H20 = (Weight H)x2 + Weight 0= 1 g/mol x 2 + 16 g/mol=
Weight 1 mol H20 = 18g/mol
18g---------6,02x10e23 molecules
0,10g-------x=(0,10gx6,02x10e23 molecules)/18g=3,34x10e21 molecules