Unit 1 Practice Test: Gen Chem Review

1. Using the rules of significant figures, calculate the following:

[A] 17

[B] 17.48

[C] 20

[D] 18

[E] 17.5

2. One kilogram contains this many grams:

[A] 10

[B] 100

[C] 1000

[D] 1/10

[E] 1/1000

3. An example of a pure substance is

[A] compounds.

[B] pure water.

[C] carbon dioxide.

[D] elements.

[E] all of these

4. The degree of agreement among several measurements of the same quantity is called __________. It reflects the reproducibility of a given type of measurement.

[A] significance

[B] error

[C] certainty

[D] precision

[E] accuracy

5. 423 Kelvin equals

[A] 150. °C

[B] 696. °F

[C] 273. °F

[D] 150. °F

[E] 696. °C

6. The melting point of lead is 327°C. What is this on the Fahrenheit scale? 
	(TF = TC ´ (9°F/5°C) + 32°F)

[A] 600°F

[B] 895°F

[C] 620.6°F

[D] 547°F

[E] 621°F

7. Generally observed behavior which can be formulated into a statement, sometimes mathematical in nature, is called a(n)

[A] measurement.

[B] experiment.

[C] natural law.

[D] observation.

[E] theory.

8. Convert 761 mi to km. (1 m = 1.094 yds, 1 mi = 1760 yds)

[A] 1.22 ´ 109 km

[B] 1220 km

[C] 832 km

[D] 696 km

[E] 1470 km

9. Which of the following is an example of a quantitative observation?

[A] The temperature of the liquid is 60°C.

[B] Solution 1 is much darker than solution 2.

[C] The piece of metal is longer than the piece of wood.

[D] The liquid in beaker A is blue.

[E] At least two of these (a-d) are quantitative observations.

10. The density of a liquid is determined by successively weighing 25, 50, 75, 100, and 125 mL of the liquid in a 250-mL beaker. Plot volume of liquid along the horizontal axis, and total mass of beaker plus liquid on the vertical axis. Which of the following is true?

[A] The plot should be curved upward because the mass of the liquid is higher in successive trials.

[B] The plot should be curved upward because the slope measures the density of a liquid.

[C] The plot should be rather linear because the slope measures the density of a liquid.

[D] The plot should be linear because the mass of the beaker stays constant.

[E] none of these

11. A 20.0-mL sample of glycerol has a mass of 25.2 grams. What is the mass of a 53-mL sample of glycerol?

12. All physical changes are accompanied by chemical changes.

[A] True

[B] False

13. Name the following compounds:
 K2Cr2O7

14. Which of the following pairs can be used to illustrate the law of multiple proportions?

[A] SO and SO2

[B] KCl and KClO2

[C] CO and CaCo3

[D] H2SO4 and H2S

[E] H2O and C12H22O11

15. All of the following are in aqueous solution. Which is incorrectly named?

[A] H3PO4, phosphoric acid

[B] H2CO3, carbonic acid

[C] H2SO4, sulfuric acid

[D] HCl, hydrochloric acid

[E] HCN, cyanic acid

16. An isotope, X, of a particular element has an atomic number of 7 and a mass number of 15. Therefore,

[A] X is an isotope of nitrogen.

[B] X has 8 neutrons per atom.

[C] X has an atomic mass of 14.0067.

[D] a and b

[E] a, b, and c

17. The correct name for Ca2+ is

[A] calcium ion

[B] calcium (I) ion

[C] monocalcium ion

[D] calcium

[E] calcium (II) ion

18. Which one of the following statements about atomic structure is false?

[A] The protons and neutrons in the nucleus are very tightly packed.

[B] Almost all of the mass of the atom is concentrated in the nucleus.

[C] The electrons occupy a very large volume compared to the nucleus.

[D] The number of protons and neutrons is always the same in the neutral atom.

[E] All of these statements (a-d) are true.

19. Complete the following table.

20. Write the formula for:
 iron (III) oxide

21. Name the following compounds:
 AgCl

22. What are the forms of elemental carbon?

[A] diamond, graphite, and carbonite

[B] graphite, diamond, and buckminsterfullerene

[C] graphite and buckminsterfullerene

[D] diamond and buckminsterfullerene

[E] graphite and diamond

23. The average mass of a carbon atom is 12.011. Assuming you were able to pick up only one carbon unit, the chances that you would randomly get one with a mass of 12.011 is

[A] 0.011%.

[B] greater than 50%.

[C] about 12%.

[D] 12.011%.

[E] 0%.

24. All of the following are characteristics of nonmetals except:

[A] do not have a shiny (lustrous) appearance

[B] tend to form negative ions in chemical reactions with metals

[C] poor conductors of electricity

[D] often bond to each other by forming covalent bonds

[E] appear in the upper left-hand corner of the periodic table

25. How many atoms (total) are there in one formula unit of Ca3(PO4)2?

26. Balanced chemical equations imply which of the following?

[A] Numbers of molecules are conserved in chemical change.

[B] Numbers of atoms are conserved in chemical change.

[C] Volume is conserved in chemical change.

[D] b and c

[E] a and b

27. A given sample of xenon fluoride contains molecules of a single type XeFn, where n is some whole number. Given that 9.03 ´ 1020 molecules of XeFn weigh 0.311 g, calculate n.

[A] 2

[B] 1

[C] 4

[D] none of these

28. The characteristic odor of pineapple is due to ethyl butyrate, a compound containing carbon, hydrogen, and oxygen. Combustion of 2.78 g of ethyl butyrate leads to formation of 6.32 g of CO2 and 2.58 g of H2O. The properties of the compound suggest that the molar mass should be between 100 and 150. What is the molecular formula?

29. Naturally occurring iron contains 5.82% Fe, 91.66% Fe, 2.19% Fe, and 0.33% Fe. The respective atomic masses are 53.940 amu, 55.935 amu, 56.935 amu, and 57.933 amu. Calculate the average atomic mass of iron.

30. What is the coefficient for water when the following equation is balanced?
	As(OH)3(s) + H2SO4(aq) ® As2(SO4)3(aq) + H2O(1)

[A] 6

[B] 12

[C] 4

[D] 1

[E] 2

31. The empirical formula of styrene is CH; its molar mass is 104.1. What is the molecular formula of styrene?

[A] C2H4

[B] C10H12

[C] C8H8

[D] C6H6

[E] none of these

32. How many grams are in a 6.94-mol sample of sodium hydroxide?

[A] 278 g

[B] 131 g

[C] 169 g

[D] 40.0 g

[E] 34.2 g

33. In a metallurgical process the mineral pyrite, FeS2, is roasted in air:
	FeS2 + O2 ® Fe2O3 + SO2
The SO2 is then converted into H2SO4 in the following reactions:
	
Assuming the mineral is 24.0% FeS2 and the remainder is inert, what mass of H2SO4 is produced if 155 g of the mineral is used?

34. Given the equation 3A + B ® C + D, you react 2 moles of A with 1 mole of B. Which of the following is true?

[A] Neither reactant is limiting.

[B] B is the limiting reactant because 3 A molecules react with 1 B molecule.

[C] A is the limiting reactant because of its higher molar mass.

[D] B is the limiting reactant because you have fewer moles of B than A.

[E] A is the limiting reactant because you need 3 moles of A and have 2.

35. Consider the fermentation reaction of glucose:
	C6H12O6 ® 2C2H5OH + 2CO2
A 1.00-mole sample of C6H12O6 was placed in a vat with 100 g of yeast. If 46 grams of C2H5OH was obtained, what was the percent yield of C2H5OH?

[A] 50.%

[B] 56%

[C] 42%

[D] 100%

[E] none of these

Answers

Reference: 1.5
[1] [A]

Reference: 1.3
[2] [C]

Reference: 1.9
[3] [E]

Reference: 1.4
[4] [D]

Reference: 1.7
[5] [A]

Reference: 1.5,1.7
[6] [E]

Reference: 1.2
[7] [C]

Reference: 1.6
[8] [B]

Reference: 1.2
[9] [A]

Reference: [1.52]
[10] [C]

Reference: 1.6
[11] (25.2 g/20.0 mL) (53 mL) = 66.8 g = 67 g to 2 sig. figs.

Reference: 1.9
[12] [B]

Reference: 2.8
[13] potassium dichromate

Reference: 2.2
[14] [A]

Reference: 2.8
[15] [E]

Reference: 2.5
[16] [D]

Reference: 2.8
[17] [A]

Reference: 2.4,5
[18] [D]

Reference: 2.5
[19] 

Reference: 2.8
[20] Fe2O3

Reference: 2.8
[21] silver chloride

Reference: 2.8
[22] [B]

Reference: 2.5
[23] [E]

Reference: 2.7
[24] [E]

Reference: 2.8
[25] 13

Reference: 3.6
[26] [B]

Reference: 3.3
[27] [C]

Reference: 3.5
[28] C6H12O2

Reference: 3.1
[29] 55.85 amu

Reference: 3.7
[30] [A]

Reference: 3.5
[31] [C]

Reference: 3.3
[32] [A]

Reference: 3.8
[33] 60.8 g H2SO4

Reference: 3.9
[34] [E]

Reference: 3.9
[35] [A]