chem test

Chapter 1: The Chemical World

1. Chemistry is best defined as the study of:

A. Living organisms only
B. Matter, its composition, properties, and changes
C. Energy and motion only
D. The Earth's geological history

2. Which is a qualitative observation?

A. The liquid has a mass of 25.4 g
B. The temperature is 37.0°C
C. The solution is blue
D. The volume is 15.0 mL

3. Which is a quantitative observation?

A. The solid is shiny
B. The liquid is colorless
C. The sample has a mass of 14.2 g
D. The substance smells sweet

4. A scientist proposes that increasing temperature will increase the rate of a chemical reaction. This is a:

A. Law
B. Theory
C. Hypothesis
D. Measurement

5. A hypothesis must be:

A. Proven true
B. Testable
C. A mathematical equation
D. Based only on previous laws

6. A scientific law primarily:

A. Explains why something happens
B. Summarizes observations and predicts future observations
C. Is always proven absolutely
D. Is a guess about an experiment

7. A scientific theory:

A. Is simply an opinion
B. Explains why or how observations occur
C. Can never change
D. Is less supported than a hypothesis

8. Which branch of chemistry focuses primarily on carbon-containing compounds?

A. Inorganic chemistry
B. Analytical chemistry
C. Organic chemistry
D. Physical chemistry

9. Which branch of chemistry focuses on identifying, separating, and determining the amounts of substances?

A. Analytical chemistry
B. Organic chemistry
C. Biochemistry
D. Physical chemistry

10. The study of chemical processes occurring in living organisms is:

A. Inorganic chemistry
B. Biochemistry
C. Physical chemistry
D. Analytical chemistry

Chapter 2: Measurement & Problem Solving

11. Which is an SI base unit for mass?

A. Gram
B. Milligram
C. Kilogram
D. Pound

12. Which is the SI base unit for length?

A. Centimeter
B. Meter
C. Kilometer
D. Millimeter

13. Which is the SI base unit for temperature?

A. Celsius
B. Fahrenheit
C. Kelvin
D. Joule

14. Which is the SI base unit for time?

A. Minute
B. Hour
C. Second
D. Day

15. Which is the SI base unit for amount of substance?

A. Gram
B. Mole
C. Liter
D. Newton

Significant Figures

16. How many significant figures are in 456?

A. 2
B. 3
C. 4
D. 6

17. How many significant figures are in 0.00450?

A. 2
B. 3
C. 4
D. 5

18. How many significant figures are in 405?

A. 2
B. 3
C. 4
D. 5

19. How many significant figures are in 450?

A. 1
B. 2
C. 3
D. 4

20. How many significant figures are in 450.?

A. 2
B. 3
C. 4
D. 5

21. How many significant figures are in 0.000700?

A. 1
B. 2
C. 3
D. 4

22. Which zeros are generally not significant?

A. Zeros between nonzero digits
B. Trailing zeros after a decimal
C. Leading zeros
D. All zeros

Significant-Figure Calculations

23. Calculate using the correct number of significant figures:

2.5×3.42

A. 8.55
B. 8.6
C. 8.550
D. 9

24. Calculate:

12.11+3.2

A. 15.31
B. 15.3
C. 15.30
D. 15

25. Calculate:

38.64×105.93

A. 4094.3352
B. 4094.3
C. 4094
D. 4100

26. Calculate:

100.0÷4.00

A. 25
B. 25.0
C. 25.00
D. 25.000

Metric Conversions

27. Convert 4.5 m → cm.

A. 0.045 cm
B. 45 cm
C. 450 cm
D. 4500 cm

28. Convert 725 cm → m.

A. 0.725 m
B. 7.25 m
C. 72.5 m
D. 7250 m

29. Convert 3.2 km → m.

A. 32 m
B. 320 m
C. 3200 m
D. 32,000 m

30. Convert 3500 mg → g.

A. 0.35 g
B. 3.5 g
C. 35 g
D. 350 g

31. Convert 2.75 kg → g.

A. 27.5 g
B. 275 g
C. 2750 g
D. 27,500 g

Volume Conversions

32. Which relationship is correct?

A. 1 L = 100 cm³
B. 1 L = 1000 cm³
C. 1 L = 10 cm³
D. 1 L = 10,000 cm³

33. Convert 450 cm³ → L.

A. 0.045 L
B. 0.450 L
C. 4.50 L
D. 450 L

34. Convert 3.2 L → cm³.

A. 32 cm³
B. 320 cm³
C. 3200 cm³
D. 32,000 cm³

35. Convert 750 mL → L.

A. 0.0750 L
B. 0.750 L
C. 7.50 L
D. 750 L

36. Which conversion is correct?

A. 1 mL = 10 cm³
B. 1 mL = 100 cm³
C. 1 mL = 1 cm³
D. 1 mL = 0.1 cm³

Dimensional Analysis

37. When setting up a conversion factor, which unit should generally be placed on the bottom?

A. The unit you want
B. The unit you currently have and want to cancel
C. The SI unit
D. The largest unit

38. Which conversion factor correctly converts kilograms to grams?

A. 1 g1000 kg
B. 1 kg1000 g
C. 1000 g1 kg
D. 1000 kg1 g

39. When converting cubic inches to cubic centimeters, which conversion factor should be cubed?

A. 1 in2.54 cm
B. 2.54 cm1 in
C. Both A and B can be cubed depending on the direction
D. Neither

Density

40. Which equation represents density?

A. D=M×V
B. D=M/V
C. D=V/M
D. D=M+V

41. A sample has a mass of 25.0 g and a volume of 5.0 mL. What is its density?

A. 0.20 g/mL
B. 5.0 g/mL
C. 12.5 g/mL
D. 125 g/mL

42. An object has a density of 4.0 g/cm³ and a mass of 20 g. What is its volume?

A. 5.0 cm³
B. 16 cm³
C. 80 cm³
D. 0.20 cm³

43. A substance has a density of 2.0 g/mL and a volume of 15 mL. What is its mass?

A. 7.5 g
B. 13 g
C. 17 g
D. 30 g

Chapter 3: Matter

44. Matter is anything that:

A. Has energy
B. Has mass and occupies space
C. Can be seen
D. Is a solid

45. Which state of matter has a definite volume but takes the shape of its container?

A. Solid
B. Liquid
C. Gas
D. Plasma

46. Which phase change is solid → liquid?

A. Freezing
B. Melting
C. Condensation
D. Sublimation

47. Which phase change is liquid → gas?

A. Condensation
B. Freezing
C. Vaporization
D. Deposition

48. Which phase change is solid → gas?

A. Melting
B. Sublimation
C. Deposition
D. Condensation

49. Which phase change is gas → solid?

A. Sublimation
B. Vaporization
C. Deposition
D. Freezing

50. Which statement is correct?

A. Adding energy generally moves matter from gas → liquid → solid
B. Removing energy generally moves matter from solid → liquid → gas
C. Adding energy generally moves matter from solid → liquid → gas
D. Endothermic processes release energy into the surroundings