Use the periodic table to calculate the molar mass of each compound below. Give your answer to the
correct number of significant figures.
Sodium hydroxide (NaOH): g/mol
Water (H20): g/mol
Glucose (C6H1206): g/mol
Calcium sulfate (CaSO4): g/mol
Magnesium phosphate (Mg3(PO4)2):
g/mol

NaOH:  22.99 + 16.00 + 1.008 = 40.00 g/mol

H₂O:  2(1.008) + 16.00 = 18.02 g/mol

C₆H₁₂O₆:  6(12.01) + 12(1.008) + 6(16.00) = 180.2 g/mol

CaSO₄:  40.08 + 32.06 + 4(16.00) = 136.1 g/mol

Mg₃(PO₄)₂:  3(24.33) + 2(30.97) + 8(16.00) = 262.9 g/mol

The numbers I added up are the atomic numbers you can find on the periodic table.  Multiply the atomic numbers by however many atoms of a element you have.

in scientific notation, the value of the  speed of light in a vacuum

  will be written as 2.995 * 10^8. when this value is represented in the form of

  a * 10^b, then, a = 2.995 and b = 8.

the value of the speed of light in a vacuum given above can also be rounded up to approximately 300000000. in this case, the scientific notation will be written as 3 *10^8.