Answer:
1. Add all the molar masses of what composes sodium hydroxide (NaOH)
Na x 1 = 22.989 g/mol
O x 1 = 15.999 g/mol
H x 1 = 1.008 g/mol
Total molar mass of sodium hydroxide is 39.996 g/mol
2. First you look up molar masses in a data book, periodic table, etc.
Write down the molar mass of each element. In this case:
Magnesium: 24.305 grams per mole
Chlorine: 35.45 grams per mole
Then write the chemical formula of magnesium chloride down. I assume you know how to determine chemical formulas of simple compounds.
MgCl2
To determine the molar mass multiply the molar mass of each element in the compound by the number of atoms of each element in the compound.
(24.305gmol^-1 x 1) + (35.45gmol^-1 x 2)
= 95.205 grams per mole.
