Question 1

Which of the following statements best describes a compound?

Accepted Answer

A substance formed from two or more different elements in a definite ratio.

Question 2

Which property is intensive and does NOT depend on the amount of substance present?

Accepted Answer

Temperature

Question 3

A student measures the mass of a cube as 9.20 g and its edge length as 1.50 cm. What is the density of the cube in $$g/cm^3$$?

Accepted Answer

$$6.13\ g/cm^3$

Question 4

Which of the following is a chemical property?

Accepted Answer

Flammability

Question 5

Which separation technique would you use to separate a mixture of sand and salt water?

Accepted Answer

Filtration

Question 6

Convert 155 lbs to kilograms using the conversion factor $$1\ kg = 2.205\ lbs. $$Report your answer to the correct number of significant figures.

Accepted Answer

$$70.3\ kg$$

Question 7

Which of the following is a heterogeneous mixture?

Accepted Answer

Orange juice with pulp

Question 8

A car travels 220 miles and gets 30 miles per gallon. How many gallons of gas are used?

Accepted Answer

$$7.3\ gallons$$

Question 9

Which of the following numbers has four significant figures?

Accepted Answer

4.061

Question 10

Which of the following is an example of a physical change?

Accepted Answer

Melting ice

Question 11

Express the number 0.000000000074 m in scientific notation.

Accepted Answer

$$7.4 	imes 10$$^{-11}$$\ m$$

Question 12

Which metric prefix corresponds to $$10^{-6}$$?

Accepted Answer

Micro

Question 13

A procedure requires 20.0 g of ethanol. If the density of ethanol is $$0.789\ g/cm^3$, what volume (in mL) should be delivered?

Accepted Answer

$$25.4\ mL$$

Question 14

Which of the following is a derived SI unit?

Accepted Answer

Liter

Question 15

Which of the following statements about significant figures is TRUE?

Accepted Answer

Trailing zeros in a number with a decimal point are significant.

Question 16

A sample of pure aspirin contains 60.0% carbon, 4.5% hydrogen, and 35.5% oxygen by mass. What type of matter is this?

Accepted Answer

Compound

Question 17

Which of the following is an exact number?

Accepted Answer

The number of students in a classroom.

Question 18

Which physical property is used to identify an unknown metal by comparing its value to a table of known substances?

Accepted Answer

Density

Question 19

Which of the following is NOT a base SI unit?

Accepted Answer

Liter

Question 20

A student adds 40 mL of water at 40°C to another beaker with 40 mL of water at 40°C. What is the resulting volume and temperature?

Accepted Answer

80 mL at 40°C

General Chemistry I: Foundations of Matter, Measurement, and Classification

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