Mole Conversions
How many moles are in 18.0 g of H2O?
1.00 mol
22.4 L
What is the percent composition of H in H₂O?
11.2 %
Define empirical formula.
The simplest whole number ratio of elements in a compound.
What is the molar mass of CO2?
44.01 g/mol
Convert 0.75 mol NaCl to grams
43.9 g
How many moles are in 44.8 L of oxygen gas at STP?
2.00 mol
What is the percent composition of C in CO₂?
27.3 %
Molecular formula if empirical is CH₂ and molar mass is 56 g/mol?
C4H8
A compound has 40.0% C, 6.7% H, 53.3% O. What’s the empirical formula?
CH2O
How many particles are in 0.25 mol of CO2?
1.51 x 1023 particles
What volume is occupied by 2.50 mol of a gas at STP?
56.0 L
Determine the % composition of each element in Na₂SO₄.
Na: 32.4%, S: 22.6%, O: 45.0%
How do you find the molecular formula from the empirical formula?
Find molar mass of empirical, divide actual molar mass by empirical mass, multiply subscripts.
How many liters are in 2.00 mol of a gas at STP?
44.8L
Convert 3.01 x 1023 molecules of O2 to grams
16 g
What volume is occupied by 2.50 mol of a gas at STP?
3.00 mol
Determine the % composition of all elements in C₆H₁₂O₆.
C: 40.0%, H: 6.7%, O: 53.3%
Empirical formula of compound with 63.5% N and 36.5% O?
N2O
What is the volume of 96.0 g of O₂ at STP?
67.2 L
How many grams are in 2.41 x 1024 molecules of H2S
137 g
A gas occupies 22.4 L at STP. What is its molar mass if it weighs 44 g?
44 g/mol
Compound has 52.2% C, 13.0% H, and 34.8% O. Empirical formula?
C₂H₆O (convert % to g, then to mol, divide by smallest)
Molecular formula if empirical is CH and molar mass is 78 g/mol?
C6H6
Find molecular formula: Empirical = CH₂O, molar mass = 180 g/mol
C₆H₁₂O₆