Unit 3 Mid-Test RETAKE

If Bryan is looking for the molar mass of H2, he has to know the ________ masses of the elements in the compound.

• Atomic

• Molar

• Molecular

• Number

The mass in grams of one mole of a substance is called:

• Atomic Mass

• Molar Mass

• Molecular Mass

• Number Mass

Calculate the molar mass of CaBr2. Ca= 40 g/mol, Br= 80 g/mol

• 100

• 200

• 300

• 400

Calculate the molar mass of PS2. P=31 g/mol, S=32 g/mol

• 75

• 85

• 95

• 105

A mass of 6.0 grams of Silicon contains ________ moles? Si= 28 g/mol

• 0.114

• 0.214

• 0.314

• 0.414

A mass of 18.0 grams of Beryllium contains ________ moles? Be= 9 g/mol

• 0.5

• 1.0

• 1.5

• 2

How many grams of SiF4 are in 5.12 moles? Si= 28 g/mol, F= 19 g/mol

• 532.48

• 632.48

• 732.48

• 832.48

A prospector pans 49.39 g of gold. How many atoms of gold does he have? Au= 197 grams/mole

• 1.15x10^23

• 2.55x10^23

• 3.15x10^23

• 4.55x10^23

A prospector pans 29.39 g of gold. How many atoms of gold does he have? Au= 197 grams/mole

• 1.98x10^22

• 8.98x10^22

• 3.98x10^23

• 7.98x10^23

A sample of potassium contains 6.02x1023 atoms. What is the mass of the sample? K= 39 g/mol

• 19

• 29

• 39

• 49