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Chemistry Final Exam - Fall 2022

Total questions: 127

Worksheet time: 27hrs 54mins

Name
Class
Date
1.
2Al + 3H2SO4 -> Al2(SO4)3 + 3H2
How many grams of aluminum sulfate would be formed if 250g H2SO4 completely reacted with aluminum?
a)
0.85 g
b)
290 g
c)
450 g
d)
870 g
2.

Complete the nuclear reaction

2760Co = ___ + -10e

a)

2556Mn

b)

2860Ni

c)

2358V

d)

2759Co

3.
What is the mole ratio of H2O to H3PO4 in the following chemical equation?   P4O10 + 6 H2O --> 4 H3PO
a)
6:4
b)
4:6
c)
1:3
d)
3:1
4.
Identify the limiting reagent when 6.00 g HCl combines with 5.00 g Mg to form MgCl2.
 
Mg +  2HCl --> MgCl2  +  H2   
 
a)
Mg
b)
H2
c)
MgCl2
d)
HCl
5.
a)
23692U
b)
23693U
c)
23492Np
d)
23493Np
6.
What is the missing isotope that will balance the following nuclear equation?
94Be  +  11H →  _____  +  42He
a)
105B
b)
105Ne
c)
63Li
d)
63C
7.
Using the following equation:
Fe2O3(s) + 3H2(g) → 2Fe(s) + 3H2O(l)
How many moles of iron can be made from  6 moles H2
a)
4 moles Fe
b)
6 moles Fe
c)
9 moles Fe
d)
2 moles Fe
8.
What particle completes this reaction?
a)
alpha particle
b)
beta particle
c)
gamma particle
d)
neutron
9.
What is the symbol for an alpha particle?
a)
42He
b)
0-1e
c)
0+1 e
d)
10n
10.

2Al + 6HCl --> 2AlCl3 + 3H2

Aluminium reacts with hydrochloric acid. How many grams of aluminum are necessary to produce 11 L of hydrogen gas at STP?

a)

13

b)

8.8

c)

0.99

d)

1.0

11.
When does a chemical reaction stop?
a)

When the scientist decides she is finished.

b)

When the quantity of the excess reactant is used up.

c)

When the quantity of the limiting reactant is used up.

d)

Chemical reactions do not stop.

e)

When the scientists sees no more steam or smoke.

12.
Fe (s) + S (l) --> FeS (s)  

In the experiment above, 7.62 g of Fe are allowed to react with 8.67 g of S.
How much FeS is formed?
a)
14.8 g
b)
12.2 g
c)
13.7 g
d)
19.9 g
13.
2Al + 3H2SO4 -> Al2(SO4)3 + 3H2
How many grams of aluminum sulfate would be formed if 250g H2SO4 completely reacted with aluminum?
a)
0.85 g
b)
290 g
c)
450 g
d)
870 g
14.
Negatively charged particles emitted from a nucleus at a high speed are ____.  
a)
alpha particle
b)
gamma rays
c)
beta particles
d)
X rays
15.
How many moles are in 19.82 g Mg? 
a)
1.226mol Mg
b)
481.7mol Mg
c)
1.000mol Mg
d)
 0.82 mol Mg
16.

Using the following equation: Fe2O3(s) + 3H2(g) → 2Fe(s) + 3H2O(l)

How many moles of iron (Fe) can be produced from six moles of H2

a)

4 moles Fe

b)

6 moles Fe

c)

9 moles Fe

d)

2 moles Fe

17.

In a chemical reaction, the mass of reactants ___.

a)

is less than the mass of products

b)

is greater than the mass of products

c)

has no relationship to the mass of products

d)

is equal to the mass of products

18.
What is the molar mass of C6H12O6?
a)

180.18 g/mol

b)

180.12 g/mol

c)

180.24 g/mol

d)

180.06 g/mol

19.

2 NaClO3 (s) --> 2NaCl (s) +3 O2 (g)  

If 12.00 moles of NaClO3 are used in this reaction, what mass of O2 is produced?

a)

256 g of O2

b)

576 g of O2

c)

288 g O2

20.
2Al + 3H2SO4 -> Al2(SO4)3 + 3H2
How many grams of aluminum sulfate would be formed if 250g H2SO4 completely reacted with aluminum?
a)
0.85 g
b)
290 g
c)
450 g
d)
870 g
21.

Absolute zero, theoretically the lowest temperature that is possible, has the value of

a)

273 K

b)

273oC

c)

0 K

d)

0 oC

22.

Two 500 mL sealed jars contain gas at STP. Jar A contains carbon monoxide. Jar B contains carbon dioxide.

a)

Jar A has less mass but the same number of particles as Jar B

b)

Jar A has less mass and fewer partilcles than Jar B

c)

Jar A has more mass but fewer particles than Jar B

d)

Jar A has more mass and more particles than Jar B

23.

77oC is the same temperature as

a)

77 K

b)

0 K

c)

350 K

d)

-196 K

24.

According to the kinetic molecular theory, the pressure of a gas

a)

decreases as the temperature increases.

b)

increases if the mass of the gas particles in a container increases.

c)

results from collisions of the gas particles with the container walls.

d)

is inversely related to the volume of the gas.

25.

1Mg + 2H2O --> Mg(OH)2 + H2

What volume of hydrogen will be produced at STP by the reaction 67.3 g of magnesium?

a)

62.0 L

b)

0.12 L

c)

2.77 L

d)

1.15 L

26.

Which of the following is a unit of pressure?

a)

kPa

b)

mm Hg

c)

torr

d)

atmospheres

e)

all of these

27.

When doing gas calculations such as when using the ideal gas equation PV = nRT , temperature must be expressed in

a)

K

b)

oC

c)

oF

d)

Pa

28.

LiOH + KCl → LiCl + KOH 

This reaction actually produced 6 grams of lithium chloride. It began with 20 grams of lithium hydroxide. What is the percent yield?

a)

16.9%

b)

5.91%

c)

1.88%

d)

12.3%

29.

If the pressure and temperature of a gas remain constant, the volume will increase if

a)

the molecular mass of the gas increases

b)

the number of moles of the gas increases

c)

the partial pressure of the gas increases

d)

the number of molecules of the gas decreases.

30.

The ideal gas law is least likely to predict the behavior of a real gas at . . .

a)

low temperatures and high pressures.

b)

low temperatures and low pressures.

c)

high temperatures and low pressures.

d)

high temperatures and high pressures.

31.

A mixture of two gases exhibits a total pressure of 1013.25 kPa. The pressure of one gas is 3 atmospheres. What amount of pressure is exerted by the other gas?

a)

5320 torr

b)

13 atm

c)

3 atm

d)

709.275 kPa

e)

The first and fourth options are correct.

32.

What is STP?

a)

0 K and 1 atm

b)

0ºC and 1 kPa

c)

0ºC and 1 atm

d)

0 K and 1 kPa

33.

What phases are present at the triple point?

a)

solid

b)

liquid

c)

gas

d)

all of the above

34.

Sublimation is ____, while condensation is ____. Deposition is ____ and vaporization is ____.

a)

gas to solid, gas to liquid, solid to gas, liquid to gas

b)

solid to gas, gas to liquid, gas to solid, liquid to gas

c)

liquid to gas, gas to solid, gas to liquid, liquid to gas

d)

gas to plasma, liquid to solid, gas to solid, liquid to gas

35.

Which of these has the largest volume at STP - 44 g of CO or 8 g of He?

a)

44 g of CO

b)

8 g of He

c)

they have the same volume

36.

The charge on a lithium ion in its ionic compound is _____.

a)

+1

b)

+2

c)

+3

d)

-1

e)

Varies

37.

A gas passing through a hole is called ...

a)

effusion

b)

diffusion

c)

compression

d)

vaporization

38.

Which one of these statements is false?

a)

The volume of a gas is the volume of its container.

b)

Most gases exist as molecular compounds.

c)

The molecules of a gas are moving quite fast.

d)

Most gases exist as free atoms or as ions.

e)

A gas's pressure changes with temperature or volume.

39.

The symbol for the rubidium ion is . . .

a)

Rb2+

b)

R+

c)

R2+

d)

Ru

e)

Rb+

40.

The substance ClO3is best described as

a)

a molecule

b)

a polyatomic ion

c)

a polyatomic molecule

d)

a mixture

41.

Ionic compounds are written with . . . .

a)

the cation first and then the anion.

b)

the anion first then the cation.

c)

Either way is acceptable.

d)

the polyatomic ion first.

42.
How do the following two elements bond together?
Pb4+  O2-       
a)
PbO
b)
Pb4O2
c)
PbO2
d)
Pb2O4
43.
Which coefficients balance this equation:
NH3  +  O2 ---->   NO  + H2O
a)
2,3,5,6
b)
5,5,4,6
c)
4,6,4,5
d)
4,5,4,6
44.

Because the overall charge in the compound Fe2O3 must be ____________, the charge of iron in Fe2O3 can be calculated as 3+.

a)

2+

b)

1+

c)

0 or zero

d)

1-

45.
What is true about the molar mass of chlorine gas?
a)
The molar mass is 35.45 g
b)
The molar mass is 70.90 g
c)
The molar mass is equal to 1 mole of chlorine atoms
d)
none of the above.
46.

Titanium (IV) oxide has the formula

a)

Ti4O

b)

TiO4

c)

Ti(IV)O

d)

TiO2

e)

Ti4O2

47.

A gas is compressed in a cylinder. Which of these variables does not change?

a)

the volume

b)

the distance between particles

c)

the pressure

d)

the number of gas particles

48.
What is the volume of liquid in this graduated cylinder?
a)
40.0 mL
b)
40.3 mL
c)
43.0 mL
d)
44.0 mL
49.
Which of the following shows the correct way to balance the chemical equation?
Fe + O2 -> Fe2O3
a)
4Fe + 3O2 -> 2Fe2O3
b)
2 Fe + 3O2 -> Fe2O6
c)
4 Fe + O6 -> 2Fe2O3
d)
None of the options are correctly balanced.
50.

How many significant figures are there? 100.00

a)

1

b)

3

c)

4

d)

5

51.

How many significant figures are there? 0.00400

a)

1

b)

3

c)

5

d)

6

52.

Round 1047.78 to three significant figures.

a)

104

b)

105

c)

1050

d)

1050.00

53.

How many protons does this isotope of titanium have? How many neutrons?

a)

48, 26

b)

22, 26

c)

22, 48

d)

22, 70

e)

48, 22

54.

What is the same when considering these electrically neutral isotopes of carbon?

a)

They all have the same mass number.

b)

The atomic number is 6.

c)

They have the same number of electrons.

d)

They have the same number of protons, electrons, and neutrons.

e)

The second and third choices are correct.

55.

If X is the symbol for an element, which of the following two symbols represent isotopes of the same element?    

I. 7735

II. 7733

III. 8137

IV. 8135 X

a)

I and II

b)

III and IV

c)

I and IV

d)

I and III

56.

Which of these is not an alloy?

a)

bronze

b)

copper

c)

brass

d)

stainless steel

57.

The isotopes of lead include lead-204, lead-206, lead-207, and lead-208.  

The average atomic mass of lead is 207.2.  

Which isotope of lead is likely to be the most abundant?

a)

204

b)

206

c)

207

d)

208

58.

76 protons and 114 neutrons

a)

Osmium-114

b)

Osmium-76

c)

Osmium-190

d)

Osmium-190.23

59.

What elements generally make a covalent bond? An ionic bond?

a)

a metal and a nonmetal, two nonmetals

b)

two nonmetals, two transition metals

c)

two metals, two nonmetals

d)

nonmetals, metal and nonmetal

e)

none of these

60.

Predict the bonds that will form between Se and Cl and between Be and F.

a)

ionic, covalent

b)

covalent, ionic

c)

covalent, metallic

d)

ionic, metallic

61.
How many electrons can the first energy level hold?
a)
1
b)
2
c)
8
d)
0
62.

Which of the pair of elements form an ionic bond?

a)

Magnesium and Oxygen

b)

Magnesium and Sodium

c)

Iron and Zinc

d)

Nitrogen and Hydrogen

63.

Using electronegativity values, determine the type of bond is formed by sulfur and bromine. The electronegativity of sulfur is 2.58, while the electronegativity of bromine is 2.96.

a)

ionic

b)

polar covalent

c)

non-polar covalent

64.
The number of _____ is most important in determining how an atoms will bond. 
a)

neutrons

b)

protons

c)

valence electrons

d)

electrons in the innermost shell

e)

isotopes

65.
What atom matches this electron configuration?
1s22s22p63s2
a)
Neon
b)
Magnesium
c)
Aluminum
d)
Potassium
66.

How many valence electrons are shown in the Lewis dot diagram?

a)

33

b)

27

c)

6

d)

9

e)

3

67.
What is the basis of a metallic bond?
a)
the attraction of neutral metal atoms.
b)
the attraction between protons and neutrons.
c)
the attraction between positive metal ions and interlocking electrons.
d)
the attraction between positive metal ions and free floating electrons.
68.
The ability of a material to be shaped in all directions without cracking or breaking.
a)
hardness
b)
ductility
c)
malleability
d)
conductivity
69.

Examine the image: How many bonds are formed looking at the model of the compound? And also indetify what type of bond is formed.

a)

2 bonds; covalent

b)

4 bonds; metallic

c)

2 bonds; ionic

d)

4 bonds; covalent

70.

Which of the following is true for ionic bonding and ionic compounds?

a)

They must be made of ions with like charges.

b)

The negative ion must be written first.

c)

Compounds must have an overall charge of zero.

d)

They are made of metals and nonmetals.

e)

The positive ion must be written first.

71.

Which was Niels Bohr's contribution to atomic theory?

a)

He documented the existence of neutrons.

b)

He proved that atoms include a nucleus.

c)

He showed that electrons exist in energy levels

d)

He performed the gold foil experiment and therefore demonstrated the existence of electrons.

e)

Bohr demonstrated that protons exist.

72.

Which part of the atomic theory did JJ Thomson prove?

a)

there are electrons

b)

electrons are in energy levels

c)

there is a nucleus

d)

cathode ray tube

73.

John Dalton wrote postulates to make the idea of the atom useful. Which postulate below was proven wrong?

a)

Elements are built from tiny indivisible and indestructible particles called atoms.

b)

The atoms of one element are different from the atoms of another element.

c)

Atoms of different elements chemically combine to form chemical compounds.

d)

During chemical reactions, atoms are rearranged.

74.

What determines the identity of the atom? What determines the reactivity of the atom?

a)

protons, protons

b)

neutrons, electrons

c)

electrons, electrons

d)

protons, electrons

e)

protons, neutrons

75.

___________ are the smallest unit of an element that maintains the properties of that element.

a)

Atoms

b)

Elements

c)

Compounds

d)

Mixtures

76.

A ____ contains a variety of elements and compounds that are not chemically combined with each other, while a ____ is a substance that has definite physical and chemical properties such as appearance, melting point, and reactivity.

a)

compound, mixture

b)

compound, pure substance

c)

mixture, compound

d)

pure substance, element

77.

Fruit Loops, pizza, and Skittles are examples of ____ mixtures, while coffee, mouthwash, and blood are examples of ____mixtures.

a)

homogeneous, heterogeneous

b)

heterogeneous, homogeneous

c)

homogeneous, pure

d)

heterogeneous, pure

78.

As you move across the Periodic Table from left to right, the atomic radius decreases.  This is because . . .

a)

the number of protons increases, so attraction to electrons increases

b)

the number of energy levels increases

c)

the number of electrons increases

d)

the atomic mass increases

e)

The number of neutrons increases, which means that there is more attraction between subatomic particles with opposite electrostatic charges.

79.

The atom with the largest atomic radius in Period 4 is ____ and the atom with the largest atomic radius in Group 18 (far right) is ____.

a)

K, Rn

b)

Kr, Rn

c)

Fe, Kr

d)

Fe, He

80.

The element in Period 6 of the Periodic Table that has the lowest ionization energy is . . .  

a)

Rn

b)

Cs

c)

Os

d)

Tm

81.

The term used to describe the amount of energy required to remove electrons from an atom is . . .

a)

electronegativity

b)

atomic number

c)

radioactivity

d)

ionization energy

e)

gravitational energy

82.

What is the name of the elements in group I, group II, group VII (second from right), and group VIII (farthest to the right) on the Periodic Table? What word do we use to describe elements that have characteristics of both metals and non-metals?

a)

alkaline earth metals, alkali metals, chalcogens, noble gases, metalloids

b)

noble gases, halogens, alkaline earth metals, alkali metals, transition metals

c)

alkali metals, alkaline earth metals, halogens, noble gases, metalloids

d)

alkaline earth metals, alkali metals, halogens, noble gases, metalloids

e)

alkali metals, alkaline earth metals, halogens, noble gases, transition metals

83.

We define electronegativity as the tendency of an atom to ____ electrons.

Its magnitude ____ increases as you move from left to right across a period on the Periodic Table of Elements and ____ as you move down a group on the Periodic Table.

a)

repel, decreases, increases 

b)

attract, increases, increases

c)

attract, increases, decreases 

d)

repel, stays the same, increases

84.

Consider the following equations.


Mg(s) + O2(g) → MgO(s)H = –602 kJ

H2(g) + O2(g) → H2O(g)H = –242 kJ


What is the ∆H value (in kJ) for the following reaction?


MgO(s) + H2(g) → Mg(s) + H2O(g)

a)

-844 kJ/mol

b)

-360 kJ/mol

c)

+360 kJ/mol

d)

+844 kJ/mol

85.

Hess' Law makes use of which principle to calculate the enthalpy change of a reaction?

a)

energy is conserved

b)

mass is conserved

c)

heat cannot be lost

d)

heat cannot be retained

e)

energy is not conserved

86.
The movement of thermal energy from an object at a higher temperature to an object at a lower temperature is called ____________.
a)

contraction

b)

expansion

c)

temperature

d)

heat

e)

cooling

87.
If the specific heat of water is 4,186 J/kg∙°C, how much heat is required to increase the temperature of 1.2 kg of water from 23 °C to 39 °C? 
a)

-80,371.2 J

b)

44,938.6 J

c)

80,371.2 J

d)

112,575.9 J

88.

A sample of iron receives 50. J of heat energy that raises the temperature of the iron by 25.0 °C.

If iron has a specific heat of 0.10 J/g°C, what is the mass of the iron sample?

a)

25 g

b)

30 g

c)

20 g

d)

50 g

89.
A reaction is performed in a beaker with a temperature probe recording the temperature changes of the reaction.  If the temperature began at 15.0 degrees Celsius and ended at 27.5 degrees Celsius. Is the reaction endothermic or exothermic?
a)
Exothermic
b)
Endothermic
90.
4.35% of all X atoms have a mass of 39.946 amu. 83.79% have a mass of 41.941 amu, 9.50% have a mass of 42.941 amu, and 2.36% have a mass of 43.939 amu. What is the average atomic mass of atom X?
a)
41.97 amu
b)
42.19 amu
c)
10.43 amu
d)
40.04 amu
91.

The process of adding an impurity to an intrinsic semiconductor is called

a)

Doping

b)

Ionization

c)

Recombination

d)

Atomic modification

92.

What is a semiconductor?

a)

A non-metal with strong covalent bonds that oppose the flow of current.

b)

A person who directs the performance of an orchestra or choir.

c)

A substance with an electrical conductivity that can act as either a conductor or an insulator depending on the circumstance.

d)

A substance that conducts only some types of electricity.

e)

A substance that is shiny but that can dissolve in water.

93.

What explains the very high melting and boiling point of water?

a)

Strong dipole-dipole bonds between water molecules

b)

Strong hydrogen bonds between water molecules

c)

Dispersion forces that are present in all molecules

d)

Asymmetrical shape of the polar bonds

e)

London dispersion forces

94.

Which substance has the weakest intermolecular forces?

a)

Substance A, boiling point of 75 °C

b)

Substance B, boiling point of 105 °C

c)

Substance C, boiling point of 25 °C

d)

Substance d, boiling point of 45 °C

95.
What information do we look for on the periodic table if we  want to examine intermolecular forces?
a)
atomic mass
b)
atomic number
c)
electronegativity
d)
ionization 
96.

Which type of solid has very strong covalent bonds between neighboring atoms? What is an example of this type of solid?

a)

ionic crystal, NaF

b)

covalent molecular crystal, ice

c)

metallic, zinc

d)

covalent network crystal, graphite

e)

none of these

97.

a. Very hard, very high melting point, nonconductors of electricity, low density.

b. High melting points, good conductors of electricity in the solid state, does not dissolve in water.

Describe the solids.

a)

ionic, metallic

b)

metallic, ionic

c)

covalent network, metallic

d)

covalent molecular, ionic

e)

covalent network, covalent molecular

98.

If I have 5600 mL of gas in a piston at a pressure of 1.5 atm and compress the gas until its volume is 4.8 L, what will the new pressure inside the piston be?

a)

1.8 atm

b)

3.27 atm

c)

1.8 L

d)

3.27 atm

99.

A weather balloon has a volume of .105 KL at 98.3 kPa when the temperature is 318 K. What is the volume at 293 K and 106.4 kPa?

a)

89.4 L

b)

0.32 L

c)

93.8 L

d)

3.13 L

100.

Determine the temperature (K) required for 0.0470 mol of gas to fill a balloon to 1.20 L under .998 atm pressure. 

a)

0 K 

b)

107 K 

c)

207 K 

d)

307 K 

101.
If the half-life of uranium-232 is 70 years, how many half-lives will it take for 10 g of it to be reduced to 1.25 g?
a)
1 half-life
b)
2 half-lives
c)
3 half-lives
d)
4 half-lives
102.

After 22,800 years, approximately what percentage of the original carbon-14 remains?

a)

15%

b)

12.5%

c)

6.25%

d)

3.125%

103.

Pb(NO3)2  +  KI --> PbI2 + KNO3  

2H2O2 ---->  2H2O + O2

What types of chemical reactions are these? 

a)

synthesis, single replacement

b)

decomposition, double replacement

c)

single replacement, combustion

d)

double replacement, decomposition 

e)

double replacement, combustion

104.

Light acts as...

a)

a wave

b)

both a wave and a particle

c)

a particle

d)

neither a wave or a particle

e)

at atom

105.

What is the energy of a quantum of light that has a frequency of 7.39 x 1014 Hz?(E=Hv)

a)

4.88 x 1019 J

b)

4.88 x 10-19 J

c)

2.22 x 1023 J

d)

2.22 x 10-23 J

106.

Certain blue lights have a frequency of 6.91 x 1014 Hz. What is the wavelength of the photons? (λ=c/v)

a)

4.34 x 1021 m

b)

4.34 x 10-21 m

c)

4.34 x 10-7 m

d)

2.07 x 1023 m

107.

A light has a wavelength of 5.06x10-5 cm. What is the frequency of the light? What is the color of the light? (v=c/λ)

a)

16.87 Hz, red

b)

5.93 Hz, orange

c)

5.93x10-14 Hz, blue

d)

5.93x1014 Hz, green

e)

none of these are correct

108.

Which of these electron configurations describes a chlorine atom?

a)

1s2s2p3s3p5

b)

1s2s2p3s3p6

c)

1s2s2p3s3p7

d)

none of these

109.

What element has this abbreviated electron configuration?

[Xe] 6s24f145d9

a)

Mercury

b)

Gold

c)

Platinum

d)

Thallium

110.

Which element would have an electron configuration that ends in s1? Which element would have an electron configuration that ends in p3

a)

Al, Br

b)

Sc, K

c)

K, P

d)

Th, Al

111.

What numbers correctly fill in the missing spaces:

As: [Ar]__s2__d10__p3

a)

4, 3, 2

b)

2, 3, 4

c)

4, 4, 4

d)

4, 3, 4

112.

What is an amorphous solid?

a)

It is a solid that does not have an ordered internal structure.

b)

It is a solid that has a crystal lattice.

c)

It is a solid that cannot change its phase.

d)

It is a solid that cannot be identified.

e)

It is a solid that has a clear unit cell and lattice structure.

113.

The smallest repeating structure of solids is the ____, which are linked in a network called a ____.

a)

unit cell, crystal

b)

unit cell, lattice

c)

crystal, pattern

d)

atom, molecule

e)

crystal, compound

114.

This is an example of...

a)

fission chain reaction

b)

fusion nuclear reaction

c)

decomposition nuclear reaction

d)

radioactive decay

e)

none of these

115.
Where does fusion occur naturally?
a)

underwater

b)

On planet Krypton

c)

in radioactive waste

d)

on the sun

116.

What occurs in both fusion and fission reactions?

a)

Small amounts of energy are converted into large amounts of matter.

b)

Small amounts of matter are converted into large amounts of energy.

c)

Heavy nuclei are split into lighter nuclei.

d)

Light nuclei are combined into heavier nuclei.

117.

Which reaction represents fission?

a)
b)
c)
d)
118.

Which reaction represents fusion?

a)
b)
c)
d)
119.

The graph shows the radioactive decay of a 50-gram sample of a radioactive isotope. What is the half-life of this isotope?  

a)

100 years

b)

150 years

c)

200 years

d)

300 years

120.

The graph shows the decay of a radioactive material over time. How long does it take for this radioactive material to decay through two half-lives?  

a)

1 x 10years

b)

5 x 10years

c)

10 x 10years

d)

40 x 10years

121.

The energy required to break a bond between two atoms in a diatomic molecule is known as ________ energy.

a)

valence

b)

bond

c)

ionization

d)

molecular

122.

What is the formal charge on the oxygen atom at the top of this Lewis dot structure?

a)

0

b)

+1

c)

-1

d)

-2

123.

According to the Octet Rule, atoms of elements react with each other in order to get ______ electrons in their outermost energy level or shell.

a)

2

b)

4

c)

8

d)

10

124.

This is a correct dot diagram for neon (Ne)

a)

true

b)

false

125.

Matter is anything that . . .

a)

emits heat or light

b)

takes up space and the quantity of it can be measured

c)

is solid or can be be condensed

d)

is a gas or a liquid and can be vaporized or condensed

e)

moves in photons and can be used to do work

126.

The reaction of magnesium with hydrochloric acid carried out in a calorimeter caused the temperature of water to change from 25.0 degrees Celsius to 36.0 degrees Celsius. In this reaction 3,760 J of energy was released . What mass of water was present?

(a)  

127.

Given the following equations and ∆Ho values, determine the heat of reaction (kJ) at 298 K for the reaction:

B2H6(g) + 6 Cl2(g) -----> 2 BCl3(g) + 6 HCl(g)

BCl3(g) + 3 H2O(l) -----> H3BO3(g) + 3 HCl(g)              ∆Ho/kJ = -112.5

B2H6(g) + 6 H2O(l) ----->  2 H3BO3(s) + 6 H2(g)              ∆Ho/kJ = -493.4

1/2 H2(g) + 1/2 Cl2(g) ----> HCl(g)                      ∆Ho/kJ = -92.3

(a)