How many moles of H2O are in 12.7 grams of H2O?
2 answers
Moles = grams/molar mass
Note that the molar mass of H2O is 18 g/mol.
If you're not sure how to calculate for the molar mass, get a periodic table and look for the individual masses of the elements present in the chemical formula. For instance, in the periodic table,
H has mass of 1 g
O has mass of 16 g
Therefore,
H2O: 2*1 + 1*16 = 18 g/mol
Then to get the number of moles, we divide the given mass by the molar mass:
12.7 / 18 = ?
hope this helps~ `u`
If you're not sure how to calculate for the molar mass, get a periodic table and look for the individual masses of the elements present in the chemical formula. For instance, in the periodic table,
H has mass of 1 g
O has mass of 16 g
Therefore,
H2O: 2*1 + 1*16 = 18 g/mol
Then to get the number of moles, we divide the given mass by the molar mass:
12.7 / 18 = ?
hope this helps~ `u`