Question: how many molecules are present in 9 gram of water and 17 gram of ammonia?
Answer: How many molecules are present in 9 g of water and 17 g of ammonia? The molar weight of H2O is 18 gram/mole, but we have 0.5 mole of water; then we have 3.01 x 10^23 molecules. The molar weight for NH3 is 14 gram/mole. So we have 1 mole of NH3 which is 6.02 x 10^23 molecules.