Chapter 9 Review - Moles & Mass-Mole Conversions

The LD₅₀ of saccharin is 17.0 g/kg. What is the lethal dose for a person who weighs 165 pounds?

• 107 mg

• 10.7 g

• 107 g

• 1.28 kg

How many mg of table salt (LD₅₀= 3000 mg/kg) would be a lethal dose for a 44 lb child?

• 60,000 mg

• 30,000 mg

• 6 g

• 3 g

Which substance is most toxic?

• table salt (LD₅₀ = 3000 mg/kg)

• aspirin (LD₅₀ = 200 mg/kg)

• cola (LD₅₀ = 127 mg/kg)

• vitamin A (LD₅₀ =1510 mg/kg)

Which substance is the least toxic?

• lorchel mushroom (LD₅₀ = 320 mg/kg)

• arsenic oxide (LD₅₀ =15 mg/kg)

• soft drink (LD₅₀ = 127 mg/kg)

• vitamin A (LD5₀ = 1510 mg/kg)

What would be the best way to get a sample of 1000 beans by using mass?

• Weigh 20 beans and collect a sample that is 100xs that

• Weigh 10 beans and collect a sample that is 1000xs that

• Weigh 1 bean and collect a sample that weighs 1000xs that

• Weigh 20 beans and collect a sample that weighs 50xs that

Which has a smaller percent error if the actual value is 126: a calculated value of 123 or 129?

• A calculated value of 129 has the smaller error.

• A calculated value of 123 has the smaller error.

• The percent error is the same for both.

• There is not enough information to answer the question.

The expected weight of 100 clips is 503 g. The actual weight is 495 g. What is percent error?

• 8.0%

• 1.6%

• 4.0%

• 0.16%

Which number is equivalent to 2.4 x 10^-5 ?

• 0.000024

• 0.0000024

• 240,000

• 2,400,000

If you have 1 mol of Al, 1 mol of Fe, 1 mol of Zn, and 1 mol of Sn, which has the most mass?

• aluminum

• iron

• zinc

• tin

Which element has a molar mass of 39.1 g/mol?

• nitrogen

• potassium

• fluorine

• neon