Chem Test 1

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Exam 1A-CHEM 1150 F12

Name___________________________________

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which of the following elements is a metal?
A) As
B) Se
C) Sn

1)
D) C

E) I

2) Determine the mass of an object that has a volume of 88.6 mL and a density of 9.77 g/mL. A) 298 g
B) 568 g
C) 907 g
D) 1100 g
E) 866 g

2)

3) A student performs an experiment to determine the density of a sugar solution. She obtains the following results: 1.71 g/mL, 1.73 g/mL, 1.67 g/mL, 1.69 g/mL. If the actual value for the density of the sugar solution is 1.40 g/mL, which statement below best describes her results? A) Her results are neither precise nor accurate.

B) Her results are both precise and accurate
C) Her results are precise, but not accurate.
D) Her results are accurate, but not precise.
E) It isn't possible to determine with the information given.

3)

4) Calculate the molar mass of H2CO3.

4)

A) 62.03 g/mol
B) 61.02 g/mol
C) 74.04 g/mol
D) 60.01 g/mol
E) 29.02 g/mol
5) What species is represented by the following information? p+ = 12
A) Si4+

n° = 14

5)

e- = 10
B) Ne

C) Mg2+

D) Si

E) Mg

6) Which of the following statements about energy is TRUE?
A) Energy is the capacity to do work.
B) Kinetic energy is the energy associated with its position or composition. C) Energy can not be converted from one type to another.
D) Systems tend to change in order to lower their kinetic energy. E) The total energy of a system does not remain constant.

6)

7) A covalent bond is best described as
A) the sharing of electrons between atoms.
B) the transfer of electrons.
C) a bond between two polyatomic ions.
D) a bond between a metal and a polyatomic ion.
E) a bond between a metal and a nonmetal.

7)

8) What answer should be reported, with the correct number of significant figures, for the following calculation? (249.362 + 41) / 63.498
A) 4.573
B) 4.57277
C) 4.6
D) 4.5728
E) 4.57

8)

1

9) Molecules can be described as
A) mixtures of two or more pure substances.
B) mixtures of two or more elements that has a specific ratio between components. C) two or more atoms chemically joined together.
D) heterogeneous mixtures.
E) homogeneous mixtures.
10) Identify the compound with ionic bonds.
A) KBr
B) CO

10)
C) H2O

D) Ne

E) O2

11) Calculate the atomic mass of element "X", if it has 2 naturally occurring isotopes with the following masses and natural abundances:
X -45
X -47

44.8776 amu
46.9443 amu

9)

11)

32.88%
67.12%

A) 46.84 amu
B) 46.26 amu
C) 44.99 amu
D) 46.34 amu
E) 45.91 amu
12) The outside temperature is 35°C, what is the temperature in K? A) 95 K
B) -238 K
C) 31 K
D) 63 K

E) 308 K

12)

13) Predict the charge that the ion formed from bromine would have. A) 2B) 4+
C) 1+
D) 2+

E) 1-

13)

14) Determine the name for CoCl 2∙6H2O. Remember that Co forms several ions.

14)

A) cobalt (I) chloride
B) cobalt (II) chloride hexahydrate
C) cobalt (II) chloride heptahydrate
D) cobalt (I) chloride heptahydrate
E) cobalt chloride hydrate
15) What is the empirical formula for C4H10O2?
A) C2H4O

B) CHO

15)

C) C2H5O

D) CH2O

16) Which of the following are examples of a chemical change? A) copper building materials develop a green patina over time B) a match burns
C) ethanol evaporates
D) Both A and B are examples of chemical change.
E) All of the above are examples of chemical change.

2

E) CHO2
16)

17) Determine the name for N2O5.

17)

A) nitrogen tetroxide
B) nitrogen (IV) oxide
C) dinitrogen pentoxide
D) nitrogen oxide
E) nitrogen (II) oxide
18) Write a balanced equation to show the reaction of aqueous aluminum acetate with aqueous ammonium phosphate to form solid aluminum phosphate and aqueous ammonium acetate. A) Al(C2H3O2)2 (aq) + (NH4)2PO4 (aq) → AlPO4 (s) + 2 NH4C2H3O2 (aq)

18)

B)...
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