Stoichiometry

Question 1

How do you find the empirical formula from percentages?

Answer 1

Percent to Mass, Mass to Moles, Divide by Small, and Multiply till Whole.

Question 2

How do you find molecular formula from empirical formula?

Answer 2

Divide the molar mass (should be given) of the molecular formula by the molar mass of the empirical formula, then multiply by the result.

Question 3

What molecules indicate the composition of a hydrocarbon in a combustion reaction?

Answer 3

CO2 and H2O. (Remember 2 to 1 ratio for hydrogen from water) When the mass of carbon, hydrogen, and oxygen is found, you can determine the molecular formula.

Question 4

What is molarity?

Answer 4

Moles per Liter

Question 5

What equation do you use to calculate dilution reactions?

Answer 5

M1V1 = M2V2