$$6 \times 10$$^{-4}$$\ \mathrm{g}$$

$$0.93\ \mathrm{cm}^3 \times 19.3\ \mathrm{g/cm}^3 = 17.95\ \mathrm{g}$$

$$3.26\ \mathrm{g/cm}^3 \times 0.350\ \mathrm{cm}^3 = 1.14\ \mathrm{g}$$

Question 1

Which of the following is NOT an SI base unit?

Accepted Answer

Joule (J)

Question 2

A laboratory thermometer reads 170 °C. What is this temperature in Kelvin?

Accepted Answer

$$170 + 273 = 443\ \mathrm{K}$$

Question 3

Which of the following correctly expresses 0.0006 g in scientific notation?

Accepted Answer

$$6 	imes 10$$^{-4}$$\ \mathrm{g}$$

Question 4

A student finds a metal with a mass of 614 g and a volume of 78 cm$$^3. $$What is its density?

Accepted Answer

$$\frac{614\ \mathrm{g}}{78\ \mathrm{cm}^3} = 7.87\ \mathrm{g/cm}^3$$

Question 5

Which of the following is the correct SI derived unit for pressure?

Accepted Answer

Pascal (Pa)

Question 6

A plastic ball has a mass of 15.8 g and a volume of 19.7 cm$$^3. $$Will it sink or float in gasoline (density = 0.70 g/cm$$^3$$)?

Accepted Answer

It will sink, because its density $$= \frac{15.8}{19.7} = 0.80\ \mathrm{g/cm}^3 is $$greater than gasoline.

Question 7

Which of the following numbers has 4 significant figures?

Accepted Answer

0.004560

Question 8

A piece of gold has a volume of 0.93 cm$$^3$$ and a density of 19.3 g/cm$$^3. $$What is its mass?

Accepted Answer

$$0.93\ \mathrm{cm}^3 	imes 19.3\ \mathrm{g/cm}^3 = 17.95\ \mathrm{g}$$

Question 9

Which of the following is the correct relationship for converting Celsius to Kelvin?

Accepted Answer

$$K = ^\circ C + 273$$

Question 10

A measurement is recorded as 0.02030 g. How many significant figures does it have?

Accepted Answer

5

Question 11

Which of the following is the correct SI prefix and factor for 'micro-'?

Accepted Answer

micro- ($$\mu$$), $$10^{-6}$$

Question 12

A sample of silicon has a mass of 62.9 g and a density of 2.33 g/cm$$^3. $$What is its volume?

Accepted Answer

$$\frac{62.9\ \mathrm{g}}{2.33\ \mathrm{g/cm}^3} = 27.0\ \mathrm{cm}^3$$

Question 13

Which of the following is the correct SI prefix for $$10^9$$?

Accepted Answer

Giga- (G-)

Question 14

When adding 12.11, 18.0, and 1.013, what is the correct answer with the proper number of significant figures?

Accepted Answer

31.1

Question 15

A substance has a density of 3.26 g/cm$$^3$$ and a volume of 0.350 cm$$^3. $$What is its mass?

Accepted Answer

$$3.26\ \mathrm{g/cm}^3 	imes 0.350\ \mathrm{cm}^3 = 1.14\ \mathrm{g}$$

Question 16

Which of the following is the correct SI prefix and factor for 'centi-'?

Accepted Answer

centi- (c-), $$10^{-2}$$

Question 17

Which of the following statements about significant figures is TRUE?

Accepted Answer

Zeros between two significant digits are always significant.

Question 18

A hospital sterilizes instruments at 170 °C. What is this temperature in Kelvin, and why is this conversion important in scientific communication?

Accepted Answer

$$170 + 273 = 443\ \mathrm{K}$$; Kelvin is the SI unit, ensuring consistency in scientific data.

Question 19

Which of the following best describes the purpose of dimensional analysis in chemistry?

Accepted Answer

It is a method of problem solving that uses conversion factors to move from one unit to another.

Measurements in Chemistry: SI Units, Conversions, and Scientific Notation

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