Measurement and Uncertainty Quiz

What is the value of the temperature change?

Initial temperature: 2.0 ± 0.1 °C

Final temperature: 15.0 ± 1.0 °C

• 13.0 ± 0.1 °C

• 13.0 ± 0.9 °C

• 13.0 ± 1.0 °C

• 13.0 ± 1.1 °C

How should a measurement of 5.00 g from a balance be recorded?

• 5.00 ± 0.1 g

• 5.00 ± 0.01 g

• 5.00 ± 1 g

• 5.00 ± 0.001 g

What are the absolute and percentage uncertainties for the change in mass?

Initial mass: 22.35 ±0.05 g

Final mass: 42.35 ±0.05 g

• A

• B

• C

• D

Aspirin, one of the most widely used drugs in the world, can be prepared according to the equation given below.

A student reacted some salicylic acid with excess ethanoic anhydride. Impure solid aspirin was obtained by filtering the reaction mixture. Pure aspirin was obtained by recrystallization. The following table shows the data recorded by the student.

State the number of significant figures associated with the mass of pure aspirin obtained.

• 1

• 2

• 3

Aspirin, one of the most widely used drugs in the world, can be prepared according to the equation given below.

A student reacted some salicylic acid with excess ethanoic anhydride. Impure solid aspirin was obtained by filtering the reaction mixture. Pure aspirin was obtained by recrystallization. The following table shows the data recorded by the student.

Calculate the percentage uncertainty associated with the mass of pure aspirin.

• 0.80%

• 0.63%