Moles Test Review

A formula that shows the smallest whole number ratio of elements in a compound (the chemical formula that is reduced)

• percent composition

• empirical formula

• molecular formula

• molar mass

The mass in grams of one mole of any pure substance

• mole

• percent composition

• molecular formula

• molar mass

Which of the following is NOT equal to one mole?

• 6.02 x 10²³ water molecules

• 10.81g of Boron

• 8g of Oxygen

• 22.4 L of neon gas at STP

Find the molar mass of Al₂(SO₄)₃

• 278.03 g/mol

• 342.14 g/mol

• 134.03 g/mol

• 262.17 g/mol

How many grams are in a 3.70 mol sample of iron?

• 207 g

• 207 mol

• 0.0662 g

• 0.0662 mol

Determine the number of moles in 1.2 x 10²⁴ molecules of CO₂.

• 2.0 x 10⁴⁶ molecules

• 2.0 x 10⁴⁶ mol

• 2.0 molecules

• 2.0 mol

How many moles of air is in a ball holding 5.54 L of air?

• 0.247 L

• 0.247 mol

• 124 L

• 124 mol

Determine the number of heilum atoms in birthday balloon holding 14.2 L of air at STP.

• 3.82 x 10²³ atoms

• 1.91 x 10²⁶ atoms

• 1.05 x 10^-24 atoms

• 5.28 x 10^-22 atoms

How many grams of water can be found in a 3.40 x 10²⁴ molecule sample?

• 0.313 g

• 1.02 x 10⁴⁸ g

• 102 g

• 1.14 x 10⁴⁷ g

Find the percent composition of each element in Mg(OH)₂

• Mg = 42%, O = 27%, H = 2%

• Mg = 2%, O = 2%, H = 29%

• Mg = 59%, O = 39%, H = 2%

• Mg = 42%, O = 55%, H = 3%