HChem 512 Unit 6 Review: The Mole Concept

Front

What is the empirical formula of a compound that consists of 72.2% magnesium (Mg) and 27.8% nitrogen (N) by mass?

Back

Mg₃N₂

Front

How do you calculate the mass of 1.55 moles of nitrogen trichloride (NCl₃)?

Back

1.55 mole NCl₃ × (molar mass of NCl₃ (g) / 1 mole) = mass of NCl₃ (g)

Front

How many moles are in 47 g of KCl (molar mass = 74.551 g/mol)?

Back

0.63 mole

Front

What is the correct line of equalities for carbon dioxide (CO₂)?

Back

1 mole of CO₂ = 44.01 grams of CO₂ = 6.02 x 10²³ particles of CO₂

Front

What is the percent by mass of Br in CuBr₂?

Back

71.6%

Front

Define the mole in chemistry.

Back

The mole is a unit of measurement for amount of substance, defined as containing exactly 6.022 x 10²³ particles (atoms, molecules, etc.).

Front

What is the molar mass of a compound?

Back

The molar mass is the mass of one mole of a substance, typically expressed in grams per mole (g/mol).

Front

How do you convert grams to moles?

Back

To convert grams to moles, use the formula: moles = mass (g) / molar mass (g/mol).

Front

What is the relationship between moles and particles?

Back

1 mole of any substance contains 6.022 x 10²³ particles of that substance.

Front

What is the formula for calculating percent by mass?

Back

Percent by mass = (mass of component / total mass of compound) × 100%.