Chapter 10 Test (The Mole)

Front

The molar mass of an element is the mass of one ____ of the element.

Back

mole

Front

48.86 g of cobalt is equal to how many moles of cobalt?

Back

.8291 moles

Front

How many moles are in 3.01 x 10^22 atoms of magnesium?

Back

0.050 moles

Front

Calculate the molar mass for Al(OH)3.

Back

78.0 g/mol

Front

What percentage of the total atomic mass of lithium phosphide (Li3P) is composed of phosphorus?

Back

60%.

Front

Define 'mole' in chemistry.

Back

A mole is a unit of measurement used to express amounts of a chemical substance, defined as exactly 6.022 x 10^23 particles (atoms, molecules, etc.).

Front

What is the formula to calculate the number of moles from mass?

Back

Number of moles = mass (g) / molar mass (g/mol).

Front

What is the significance of Avogadro's number?

Back

Avogadro's number (6.022 x 10^23) is the number of atoms, molecules, or particles in one mole of a substance.

Front

How do you calculate the molar mass of a compound?

Back

Add the atomic masses of all atoms in the compound's formula.

Front

What is the molar mass of water (H2O)?

Back

18.02 g/mol.