% Comp EF MF

Front

What is the empirical formula of a compound with 72.2% magnesium and 27.8% nitrogen by mass?

Back

Mg₃N₂

Front

How do you calculate the percent composition by mass of an element in a compound?

Back

Percent composition = (mass of element in 1 mole of compound / molar mass of compound) × 100

Front

What is the percent composition by mass of magnesium in MgSO₄ (gram formula mass = 120 g/mol)?

Back

20%

Front

What is an empirical formula?

Back

An empirical formula shows the simplest whole-number ratio of atoms in a compound.

Front

Which of the following is an empirical formula: CH₃COOH, C₆H₁₂O₆, H₂O?

Back

H₂O

Front

What is the molecular formula of a compound with the empirical formula CaCl₂ and a molecular mass of 330g?

Back

Ca₃Cl₆

Front

What is the difference between empirical and molecular formulas?

Back

Empirical formulas show the simplest ratio of elements, while molecular formulas show the actual number of atoms in a molecule.

Front

How do you determine the empirical formula from percent composition?

Back

Convert percent to grams, divide by molar mass to find moles, and then simplify the ratio.

Front

What is the empirical formula of a compound with 40% carbon, 6.67% hydrogen, and 53.33% oxygen?

Back

CH₂O

Front

If a compound has a molecular formula of C₆H₁₂O₆, what is its empirical formula?

Back

CH₂O