CHEMISTRY REVIEW

Systematic errors lead to a lack of:

• accuracy in the measurement

• 1. significant digits in the measurement

• precision in the measurement

• gradation of the measuring instrument

Which of the following statements is NOT correct?

• 1. Correctness in measurement requires both accuracy and precision.

• An instrument with 2% accuracy is better than another with 5% accuracy.

• It is not possible to have precise measurements which are not accurate.

• Reproducibility and consistency are expressions that have the best precision in measurements.

How are systematic errors usually removed for an instrument?

• By replacing it

• 1. By re-calibrating it

• By using a repairing service

• By not using it for some time

 In five (5) experiments with the same objective, the values obtained are very near to each other. These values can be called ____.

• Precise

• Accurate

• Average

• Invalid

0.0000620 has eight (8) significant figures.

• True

• False

Answer explanation

0.0000620 has three (3) significant figures.

2 653 008.0 has eight (8) significant figures.

• True

• False

120 000   =   1.20 x 10⁵

• True

• False

Which of the following is the correct measurement with uncertainty using a graduated cylinder?

• 36.5 ± 1 mL

• 36.50 ± 1 mL

• 36.5 ± 0.5 mL

• 36.50 ± 0.5 mL

 Matter changing from a solid to a gas is called:

• 1. evaporation 

• 1. sublimation 

• 1. deposition 

• 1. melting

 Heat is added to the ice. What processes will it go through as it heats up?

• 1. cooling, then melting 

• 1. evaporation, then melting 

• melting, then freezing

• 1. melting, then evaporation