Grams ↔ Moles
Number of moles = (# of grams) ÷ (molar mass)
Number of grams = (# of moles) × (molar mass)
Example 1:How many moles are in 5 grams of O2?
The molar mass of O2 = 16.00 g/mole x 2 (for 2 atoms of oxygen) or 32.00 g/mole.
5 grams of O2 ÷ (32 g/mole) = 0.15625 moles
Example 2:
How many grams does 4 moles of NH3 weigh?
The molar mass of NH3 = 14.01 + (3 × 1.01) = 17.04 g/mole
4 moles × 17.04 g/mole = 68.16 grams
Number of grams = (# of moles) × (molar mass)
Example 1:How many moles are in 5 grams of O2?
The molar mass of O2 = 16.00 g/mole x 2 (for 2 atoms of oxygen) or 32.00 g/mole.
5 grams of O2 ÷ (32 g/mole) = 0.15625 moles
Example 2:
How many grams does 4 moles of NH3 weigh?
The molar mass of NH3 = 14.01 + (3 × 1.01) = 17.04 g/mole
4 moles × 17.04 g/mole = 68.16 grams
Atoms ↔ Moles
Number of moles = (# of atoms) ÷ (6.02x10^23)
Number of atoms = (# of moles) × (6.02x10^23)
Number of atoms = (# of moles) × (6.02x10^23)
Example 1:
1.65 × 1024 atoms of Magnesium?
1.65 × 1024 atoms ÷ (6.02 × 1023) = 2.74 moles of Mg
