Weekly Science Quiz #3 Grade 10

What is the molar mass of NaSO₄?

• 119.1 g/mol

• 142.1 g/mol

• 71.1 g/mol

• 101.1 g/mol

What is the molar mass of NaCl₂?

• 94 g/mol

• 58.4 g/mol

• 45 g/mol

• 85 g/mol

What is the molar mass of K(OH)₂?

• 56.1 g/mol

• 73.1 g/mol

• 37 g/mol

• 57.1 g/mol

What is the molar mass of NH₃(NO₄)

• 95 g/mol

• 80 g/mol

• 173 g/mol

• 63 g/mol

A student recovers 9.7 grams of CaCl₂ in a lab experiment. How many moles of CaCl₂ is this?

• 8.7 x 10^-2 mol CaCl₂

• 1.1 x 10³ mol CaCl₂

• 11.5 mol CaCl₂

• .13 mol CaCl₂

A certain reaction requires 3.4 moles of H₂O. How many grams of water is this?

• 61.2 grams H₂O

• 0.18 grams H₂O

• 5.3 grams H₂O

• 77.4 mol CaCl₂

A sample of Carbon is placed on a digital scale and found to have a mass of 12.0 grams. How many moles of Carbon is this?

• 12 moles

• 1 mole

• 0.1 moles

• 1.2 moles

A sample of Carbon is placed on a digital scale and found to have a mass of 12.0 grams. How many atoms of carbon are on the scale?

• 1 atom

• 6.02 x 10²³atoms

• 12 atoms

• Not Enough Information

In the "Formation of a Precipitate Lab" which substance was the precipitate?

• Sodium Carbonate

• Magnesium Carbonate

• Magnesium Sulfate

• Sodium Sulfate

In the "Formation of a Precipitate Lab" what is one reason that your yield could be too high?

• Filter paper didn't totally dry

• Some of the precipitate passed through the filter

• You added too much water

• You added to little water