Mole Benchmark

What is the relative molar mass (Mr) of NaOH?

• 368 g/mole

• 40 g/mole

• 57 g/mole

• 23 g/mole

What is the mass of one mole of (NH₄)₂CO₃?

• 144g
• 138g
• 96g
• 74g

36.0 g of Be contains how many moles?

• 0.25 mol
• 4.0 mol
• 45 mol
• 320 mol

4.0 moles of H₂O would have what mass?

• 72 g
• 23 g
• 68 g
• 4.5 g

Read the questions carefully and choose the best answer.

Avogadro’s number of atoms of any element is equivalent to

• the atomic number of that element

• 6.02 x 10²³ particles

• the mass number of that element

• 100g of that element

Read each question and choose the best answer.

The mole is an experimentally-defined unit. One mole is the number of particles found in 12.000

grams of:

• Carbon-12

• carbon-14

• oxygen

• hydrogen

The mass of one mole of an element is equal to

• its atomic number from the periodic table, but in amus.

• its atomic mass from the periodic table, but in amus.

• its atomic mass from the periodic table, but in grams.

• its atomic number from the periodic table, but in grams.

How many formula units are in 2.5 moles of NaCl?

• 1.5 x10²⁴ formula units

• 1.5 formula units

• 4.2 formula units

• 4.2 x10^-24 molecules

How many molecules are there in 31.8 moles of water?

• 5.28 x 10^-23 molecules
• 1.91 x 10²⁵ molecules
• 5.28x 10-²⁵
• 1.91 x 10²²

Determine the mass of 4.20 moles of C₆H₁₂

• 353 g

• 0.0499 g

• 337 g

• 2.53 x 10²⁴ g