wayground logo

Free Printable Worksheets

Font size

S
M
L
XL
Worksheets

Chemistry Final Practice

Total questions: 132

Worksheet time: 1hrs 6mins

Name
Class
Date
1.

If you are in lab and have longer hair, what should you do with it?

a)

Nothing its only a problem with fire

b)

Shake it out before proceeding

c)

Put on a hat

d)

Keep all long hair pulled back and tied

2.

What kind of clothes should you not wear in a science lab?

a)

Loose clothing- especially sleeves!

b)

Close toed shoes

c)

Jeans

d)

Lab coat

3.

What do you do if your lab partner catches on fire?

a)

Wrap them in the fire blanket and pat them!

b)

Dance around them screaming

c)

Move far away as possible so you don't catch on fire

d)

Don't tell anyone

4.

How do you protect your eyes during labs?

a)

Wear eye protection (goggles)

b)

Close your eyes around chemicals

c)

If you have contacts or glasses you don't have to worry

5.

How do you smell chemicals in Chemistry lab?

a)

Hold the vial way far away from your face and hope the smell doesn't get to you.

b)

Hold the vial under your nose and breathe in deeply to make sure you get a good sense of what it smells like

c)

Hold the vial under your nose and waft it

d)

Hold the vial under your nose and breathe in normally

6.

When heating or mixing a test tube, what must you remember?

a)

Neve hold a test tube over an open flame

b)

Directly mix the tube towards you so you can see it clearly

c)

Angle it away from you and your partner’s faces

d)

Add as much as you can so you can get the biggest chemical reaction

7.

How should you behave for safety during labs?

a)

PAY ATTENTION to directions- “Lab Defensively”

b)

Running around with lab equipment

c)

Leave your open flame unattended

d)

Eat food to keep up your energy

8.

What is a beaker used for in a lab?

a)

Used for holding liquids as it is not precise in measuring

b)

Used to correctly measure liquids

c)

Used to measure temperature

d)

Used to mix precise reactants fora chemical reaction

9.

What is the purpose of the background in the scientific method?

a)

Background is where you include prior knowledge or research for your investigation

b)

Background is where you include all your data from your investigation

c)

Background includes material list for procedure

d)

Background is where you analyze data in graphs

10.

What should be included in a research question or problem statement to make it testable?

a)

A prediction about results

b)

All your data and findings from your investigation

c)

Both responding and manipulated variables

d)

Background research

11.

What is a hypothesis and what do you need to include?

a)

a brief description of what you are testing, what you predict will happen and the reasoning for your prediction

b)

a detailed list of steps you will perform in the experiment

c)

a random guess about the results

d)

an educated prediction of the results

12.

What should procedures include?

a)

Directions how to collect data

b)

Logical steps to be followed to test the question, with all materials and amounts included

c)

The basic steps without any specifics to confuse

d)

Predictions about data results

13.

What are some forms of analysis of data?

a)

Errors and improvements in data

b)

Pictures and descriptions

c)

Real world application of results

d)

Graphs, calculations, and reflective questions about the data.

14.

What is the SI metric unit for Energy?

a)

Joules (J)

b)

Degrees Celsius (C)

c)

Calories (Cal)

d)

Kelvin (K)

15.

In the metric system, what does the prefix Kilo mean?

a)

1/100

b)

1/1000

c)

100

d)

1000

16.

In Scientific notation, how does writing really large numbers differ from writing really small (decimal) numbers?

a)

Large Numbers have positive exponents and decimal numbers have negative exponents.

b)

Large numbers are longer than decimal numbers

c)

Large numbers increase and small numbers decrease

d)

Large numbers have to be written before smaller numbers

17.

How are metric conversions set up?

a)

using dimensional analysis or factor label method to cancel units until desired unit is achieved.

b)

as quickly as possible to find answer

c)

with the biggest number on top

d)

using common units to cross multiply

18.

What is the volume of a substance?

a)

The sound that it makes

b)

The level of a liquid measured in a graduated cylinder

c)

The amount of matter in a substance

d)

The amount of space a substance occupies

19.

What is the mass of a substance?

a)

The sound that it makes

b)

The level of a liquid measured in a graduated cylinder

c)

The amount of matter in a substance

d)

The amount of space a substance occupies

20.

What is the correct unit for measuring density?

a)

mL/g

b)

g/mL

c)

grams

d)

mL

21.

Which of the following is a chemical property?

a)

The mass of the apple is 198 grams

b)

Iron will rust in the presence of Oxygen

c)

The grass is green and brown in color

d)

The liquid is thick and clear

22.

What are qualitative observations?

a)

Observations made of how something behaves or appears

b)

Observations made measuring data carefully

c)

Observations made by recording what you see

d)

Observations made using inferences

23.

What is matter?

a)

Anything that can be observed with the 5 senses

b)

Everything that can be found in the universe

c)

Anything that has mass and volume

d)

Anything that has mass

24.

What is a graduated cylinder?

a)
b)
c)
d)
25.

What are atoms made of?

a)

Protons and electrons

b)

Protons and neutrons

c)

Protons, neutrons, and electrons

d)

Protons only

26.

Which subatomic particle weighs the least?

a)

Protons

b)

Electrons

c)

Neutrons

d)

Nucleus

27.

What charge do protons carry?

a)

Positive

b)

Negative

c)

Neutral

d)

Even

28.

What charge do electrons carry?

a)

Positive

b)

Negative

c)

Neutral

d)

Even

29.

What charge do neutrons carry?

a)

Positive

b)

Negative

c)

Neutral

d)

Even

30.

What particles are found in an atom’s nucleus?

a)

Protons and neutrons

b)

Protons and electrons

c)

Protons only

d)

Neutrons only

31.

What is the primary way the periodic table is organized?

a)

By increasing atomic mass

b)

By increasing proton number

c)

By increasing electronegativities

d)

By increasing atomic size

32.

In the periodic table, what does the period/row tell us?

a)

What ion an atom will form

b)

How heavy it will probably be

c)

How many energy levels it has

d)

What properties it has

33.

In the periodic table, what does the group/family tell us?

a)

What ion an atom will form

b)

How many valence electrons in has

c)

What chemical properties it might have

d)

All of the Above

34.

What are valence electrons?

a)

Electrons found in the outermost energy level

b)

Electrons found closest to the nucleus

c)

Electrons with a positive charge

d)

All of the Above

35.

What is electronegativity?

a)

The distance from the center of the nucleus to the last energy level

b)

How much energy it takes to remove an electron from an atom

c)

The amount of attraction an atom has to pull an electron to itself

d)

The number of electrons an atom contains

36.

What is ionization energy?

a)

The distance from the center of the nucleus to the last energy level

b)

How much energy it takes to remove an electron from an atom

c)

The amount of attraction an atom has to pull an electron to itself

d)

The number of electrons an atom contains

37.

What is increasing trend of electronegativity?

a)

It increases across the P Table from left to right and up the groups

b)

It increases across the P Table from left to right and down the groups

c)

It increases across the P Table from right to left and up the groups

d)

It increases across the P Table from right to left and down the groups

38.

What is increasing trend of atomic radius?

a)

It increases across the P Table from left to right and up the groups

b)

It increases across the P Table from left to right and down the groups

c)

It increases across the P Table from right to left and up the groups

d)

It increases across the P Table from right to left and down the groups

39.

Where are metals found on the periodic table?

a)

On the right side of the stair step line

b)

Touching the stair step line

c)

On the left side of the stair step line

d)

Only in the very middle section

40.

Which of the following elements exists only as a diatomic molecule in pure form?

a)

Carbon

b)

Neon

c)

Sodium

d)

Oxygen

41.

How many Hydrogen atoms are in the following compound? Compound: NH4C2H3O2

a)

4

b)

7

c)

3

d)

8

42.

How many Oxygen atoms are in the following compound? Compound: Fe2(Cr2O7)3

a)

3

b)

7

c)

10

d)

21

43.

What is the amount of particles found in a mole?

a)

6.02 X 1023 particles

b)

3.01 X 1023 particles

c)

1 particle

d)

60.2 X 1023 particles

44.

What type of elements form ionic bonds?

a)

Metals and nonmetals

b)

Metals and metals

c)

Nonmetals and nonmetals

d)

Ions with ions

45.

What type of elements form covalent bonds?

a)

Metals and nonmetals

b)

Metals and metals

c)

Nonmetals and nonmetals

d)

Ions with ions

46.

Which of the following characteristics describe metallic compounds?

a)

Conducts electricity

b)

Conducts heat

c)

Malleable and Ductile

d)

All of the Above

47.

What charge do cations have?

a)

positive

b)

negative

c)

both

d)

none of the above

48.

What is the molar mass of CO2?

a)

12 grams

b)

44 grams

c)

32 grams

d)

6.02 X 1023

49.

Which bond type has the greatest differences in electronegativities?(>1.8)

a)

ionic bond

b)

covalent bond

c)

metallic bond

d)

hydrogen bond

50.

Which of the following compounds is named Iron (II) sulfate?

a)

FeS4

b)

FeSO4

c)

Fe(OH)2

d)

FeCO3

51.

Water is a _______ molecule.

a)

nonpolar

b)

ionic

c)

polar

d)

network covalent

52.

Conductivity is the ability to

a)

transfer heat or electrons through as substance

b)

prevent heat or electrons to transfer through a substance

c)

absorb heat or electrons into a substance

d)

emit heat or electrons from a substance

53.

Which of the following compounds will dissolve in water?

a)

Polar Compounds

b)

Ionic Compounds

c)

Nonpolar Compounds

d)

Both A and B

54.

Which of the following reactions reflects a balanced equation?

a)

2Na + 2H2O ---> 2NaOH + H2

b)

Na2O2 + H2O ---> 2NaOH + O2

c)

2Zn + HCl ---> ZnCl2 + H2

d)

2KClO3 ---> KCl + 3O2

55.

What is a precipitate?

a)

When a liquid and a solid react to form a gas

b)

The process where molecules separate depending on size and polarity

c)

When a solute completely dissolves in water to form a liquid solution

d)

A solid that forms when two aqueous solutions react to form a product that is not soluble in water

56.

What is an aqueous solution?

a)

When a liquid and a solid react to form a gas

b)

The process where molecules separate depending on size and mass

c)

When a solute completely dissolves in water

d)

A solid forming when two aqueous solutions react to form a product that is not soluble in water

57.

What is Kinetic Energy?

a)

The energy of an object in motion

b)

The energy stored within a substance

c)

The energy released as heat

d)

The energy of the universe

58.

What is Potential Energy?

a)

The energy of an object in motion

b)

The energy stored within a substance

c)

The energy released as heat

d)

The energy of the universe

59.

In an endothermic reaction,

a)

heat is absorbed by the reaction

b)

heat is released by the reaction

c)

heat is in equilibrium

d)

heat is not a factor in this type of reaction

60.

When bonds are formed,

a)

energy is absorbed

b)

energy is released

c)

energy is in equilibrium

d)

energy is not a factor in this process

61.

When bonds are broken,

a)

energy is absorbed

b)

energy is released

c)

energy is in equilibrium

d)

energy is not a factor in this process

62.

In order to change phases of matter, one must

a)

Move the object

b)

Change the energy of the system

c)

Calculate it’s mass and volume

d)

Do nothing, it will occur naturally

63.

What would not be included in a conclusion?

a)

claim, evidence and reasoning for what happened in the lab

b)

real world application

c)

graph of data

d)

new questions for future investigation

e)

errors in data collection

64.

What are properties of a liquid?

a)

Definite shape and definite volume

b)

No definite shape but definite volume

c)

No definite shape or volume

d)

Electrons flying around removed from atoms.

65.

The average atomic mass of an element as shown on the periodic table is determined by

a)

The number of isotopes of the element only.

b)

The percent abundance of each isotope only.

c)

The mass of each isotope only.

d)

All of the above are used to determine the average atomic mass.

66.

Which of the following represents a chemical change?

a)

Dissolving salt in water.

b)

Boiling water for tea.

c)

Burning a piece of paper.

d)

Melting an ice cube.

67.

The smallest form of matter that still holds its original properties is called a(n)

a)

ion

b)

proton

c)

quark

d)

atom

68.

Noble gases are unreactive because

a)

they are gases so other atoms can't find them.

b)

they have too high of electronegativities.

c)

they have a full outer energy level of electrons.

d)

they have all the protons they need to be stable.

69.

The “Octet rule” says that atoms are more stable when they have...

a)

An atomic number that ends in eight

b)

Eight protons in the outer energy level

c)

Eight electrons in the outer energy level

d)

Eighty electrons total

70.

What is an ion?

a)

A type of bond

b)

A charged particle

c)

An atom that can never be found alone

d)

A molecule composed of 2 atoms.

71.

Which of the following best describes covalent bonding?

a)

The sharing of one or more pairs of electrons between two atoms.

b)

The transfer of one or more electron causing oppositely charged particles to attract.

c)

Delocalized electrons that free flow around cations.

d)

The sharing of one or more protons between two atoms.

72.

If you dissolved 10g of salt into water, the salt would be called the…

a)

Solvent

b)

Solute

c)

Solution

d)

Catalyst

73.

In a chemical equation, the reactants belong…

a)

On the left side of the equation, with products on the right

b)

On the right side of the equation, with products on the left

c)

Over the arrow to show that they are not used up in the reaction

d)

The reactants are not included in the chemical equations

74.

By rule in stoichiometry, you must always start with:

a)

Grams of a known substance

b)

The theoretical yield

c)

The moles of your product

d)

A balanced equation

75.

In an exothermic reaction,

a)

heat is absorbed by the reaction

b)

heat is released by the reaction

c)

heat is in equilibrium

d)

heat is not a factor in this type of reaction

76.

Classify the following reaction:

CH4 + 2O2 → CO2 + 2H2O

a)

Combination

b)

Single Displacement

c)

Double Displacement

d)

Combustion

e)

Decomposition

77.

Classifying the following reaction:

2H2O → 2H2 + O2

a)

Combination

b)

Single Displacement

c)

Double Displacement

d)

Combustion

e)

Decomposition

78.

Classify the following reaction:

Zn + 2HCl → H2 + ZnCl2

a)

Combination

b)

Single Displacement

c)

Double Displacement

d)

Combustion

e)

Decomposition

79.

Classify the following type of reaction:

2KCl + 3O2→ 2KClO3

a)

Combination

b)

Single Displacement

c)

Double Displacement

d)

Combustion

e)

Decomposition

80.

Classify the following reaction:

H2SO4 + 2NaOH → Na2SO4 + 2H2O

a)

Combination

b)

Single Displacement

c)

Double Displacement

d)

Combustion

e)

Decomposition

81.

Which of the following represents a physical change?

a)

Melting of ice

b)

Burning of wood

c)

Rusting of nail

d)

Rotting of fruit

82.

What are properties of a solid?

a)

Definite shape and definite volume

b)

No definite shape but definite volume

c)

No definite shape or volume

d)

Electrons flying around removed from atoms.

83.

What is the correct reading for the volume of water in the graduated cylinder shown in the picture below?

a)

43 ml

b)

43.5 ml

c)

44 ml

d)

45 ml

84.

How many bonds does a carbon atom often form in a covalent compound?

a)

1

b)

2

c)

3

d)

4

85.

How many bonds does a nitrogen atom often form in a covalent compound?

a)

1

b)

2

c)

3

d)

4

86.

Which of the structural formulas below could exist according to the HONC 1234 rule?

a)
b)
c)
d)
87.

What must happen to a solid material before a person is able to smell it?

a)

Molecules break apart into individual functional groups.

b)

Molecules melt to the liquid state.

c)

Molecules vaporize to the gas state.

d)

Molecules clump together in the air.

88.

What structural component results in a fishy smell?

a)

long chain structure with carbon, hydrogen and oxygen

b)

carboxyl functional group

c)

nitrogen in molecular formula

d)

frying pan structure with carbon, hydrogen and oxygen

e)

ball structure with carbon, hydrogen and oxygen

89.

What structural component results in a putrid smell?

a)

long chain structure with carbon, hydrogen and oxygen

b)

nitrogen in molecular formula

c)

carboxyl functional group

d)

ball structure with carbon, hydrogen and oxygen

e)

frying pan structure with carbon, hydrogen and oxygen

90.

What structural component results in sweet smell?

a)

long chain structure with carbon, hydrogen and oxygen

b)

frying pan structure with carbon, hydrogen and oxygen

c)

nitrogen in molecular formula

d)

carboxyl functional group

e)

ball structure with carbon, hydrogen and oxygen

91.

What structural component results in minty smell?

a)

long chain structure with carbon, hydrogen and oxygen

b)

frying pan structure with carbon, hydrogen and oxygen

c)

nitrogen in molecular formula

d)

carboxyl functional group

e)

ball structure with carbon, hydrogen and oxygen

92.

What structural component results in camphor smell?

a)

long chain structure with carbon, hydrogen and oxygen

b)

frying pan structure with carbon, hydrogen and oxygen

c)

nitrogen in molecular formula

d)

carboxyl functional group

e)

ball structure with carbon, hydrogen and oxygen

93.

What is the correct interpretation of this reaction?

Cu(s) + 2HCl(aq) → CuCl2(aq) + H2(g)

a)

Hydrogen gas reacts with a solution of copper chloride to produce solid copper metal in a solution of hydrochloric acid.

b)

A solution of copper metal reacts with solid hydrochloric acid to produce a solution of copper chloride and hydrogen gas.

c)

Hydrogen gas reacts with solid copper chloride to produce solid copper metal in a solution of hydrochloric acid.

d)

Solid copper reacts with a solution of hydrochloric acid to produce a solution of copper chloride and hydrogen gas.

94.

H2O(s) → H2O(g) is an example of _____.

a)

a combination reaction

b)

a decomposition reaction

c)

a physical change

d)

a chemical change

95.

Suppose you mixed solid calcium metal, Ca with hydrochloric acid, HCl(aq) in an open container. If the mass of the reactants were measured and then the mass of the products in the container were measured after the reaction has completed, what would be the result?

Ca(s) + 2HCl(aq) → CaCl2(aq) + H2(g)

a)

The mass will stay the same.

b)

The mass will increase.

c)

The mass will decrease.

d)

There is not enough information to answer the question.

96.

Jake measures the weight of one bottle cap as 5.35 grams, so he calculates that the weight of 100 bottle caps will be 535 grams. The actual weight of 100 bottle caps is 518 grams. What is Jake’s percent error?

a)

9.7%

b)

3.2%

c)

1.6%

d)

0.032%

97.

What are quantitative observations?

a)

observation about how something appears or behaves

b)

observations that include numbers

c)

observations made from smelling a substance

d)

observations about color changes that take place

98.

Elements in group 1A on the periodic table are known as

a)

noble gases

b)

halogens

c)

alkali metals

d)

alkaline earth metals

99.

Elements in group 7A are known as

a)

halogens

b)

noble gases

c)

alkali metals

d)

alkaline earth metals

100.

Elements in group 1-8B are known as

a)

noble gases

b)

alkaline earth metals

c)

halogens

d)

transition metals

101.

Elements in group 2A are known as

a)

halogens

b)

noble gases

c)

alkaline earth metals

d)

transition metals

102.

Elements in group 8A are known as

a)

halogens

b)

alkaline earth metals

c)

noble gases

d)

alkali metals

103.

If you have 1 mol of aluminum, 1 mol of iron, 1 mol of zinc, and 1 mol of tin, which has the most mass?

a)

aluminum

b)

iron

c)

zinc

d)

tin

104.

Which contains the most atoms: 20 g of aluminum, 20 g of iron, 20 g of zinc, or 20 g of tin?

a)

Aluminum

b)

Iron

c)

Zinc

d)

Tin

105.

How can you convert the mass of a substance to moles?

a)

Divide the mass of the substance in grams by its molar mass.

b)

Divide the molar mass of the substance by the mass of the substance in grams.

c)

Multiply the molar mass of the substance by the mass of the substance in grams.

d)

Multiply the mass of the substance in grams by its molar mass.

106.

How many moles of phosphorus trichloride, PCl3 molecules are there in an 80.0 gram sample?

a)

0.085 mol

b)

0.583 mol

c)

1.72 mol

d)

137.5 mol

107.

How many atoms are there in 1 mole of SO2?

a)

6.02 × 1023 atoms

b)

1.80 × 1024 atoms

c)

6.02 × 1024 atoms

d)

1.80 × 1069 atoms

108.

Which of the following will increase the rate of reaction between a solid and a solution?

a)

Increase the size of the solid particles.

b)

Add water to the solution.

c)

Heat the mixture.

d)

Let mixture sit undisturbed.

109.

What happens when you add a catalyst to a chemical reaction?

a)

The activation energy goes up.

b)

The catalyst reacts to form a new compound.

c)

The activation energy goes down.

d)

The catalyst is consumed.

110.

Which scientist created the modern periodic table?

a)

Niels Bohr

b)

John Dalton

c)

Ernest Rutherford

d)

Dmitri Mendeleev

e)

JJ. Thomson

111.

Which scientist discovered the electron?

a)

Niels Bohr

b)

John Dalton

c)

Ernest Rutherford

d)

Dmitri Mendeleev

e)

JJ Thomson

112.

Which scientist created a model of the atom with electron orbiting the nucleus like planets orbit the sun?

a)

Niels Bohr

b)

John Dalton

c)

Dmitri Mendeleev

d)

Ernest Rutherford

e)

JJ Thomson

113.

Which scientist came up with the first atomic theory with four parts?

a)

Niels Bohr

b)

John Dalton

c)

Ernest Rutherford

d)

Dmitri Mendeleev

e)

JJ Thomson

114.

Which scientist discovered the nucleus of an atom?

a)

Niels Bohr

b)

John Dalton

c)

Ernest Rutherford

d)

Dmitri Mendeleev

e)

JJ Thomson

115.

What is the transition from solid to gas called?

a)

Sublimation

b)

Melting

c)

Vaporization

d)

Condensation

e)

Freezing

116.

What is the transition from solid to liquid called?

a)

Sublimation

b)

Freezing

c)

Melting

d)

Vaporization

e)

Deposition

117.

What is the transition from liquid to gas called?

a)

Sublimation

b)

Freezing

c)

Vaporization

d)

Melting

e)

Condensation

118.

What is the transition from gas to liquid called?

a)

Sublimation

b)

Freezing

c)

Melting

d)

Vaporization

e)

Condensation

119.

What is the transition from liquid to solid called?

a)

Sublimation

b)

Freezing

c)

Condensation

d)

Vaporization

e)

Melting

120.

Which statement below is true based on the second law of thermodynamics?

a)

Energy is transferred from colder to hotter objects during an endothermic process.

b)

Energy is transferred from colder to hotter objects during an exothermic process.

c)

Energy is never transferred during a chemical process.

d)

Energy is always transferred from hotter to colder objects.

121.

How much energy is required to raise the temperature of 55 g of iron (Cp = 0.11 cal/g°C) from 42 °C to 71 °C?

a)

175 cal

b)

500 cal

c)

5.5 cal

d)

254 cal

122.

If you have 2 moles of glucose in 4 L of solution, what is the concentration of the solution?

a)

0.5 M

b)

2 M

c)

4 M

d)

8 M

123.

Which unit should be used for solution concentration?

a)

J/g

b)

L/mol

c)

mol/L

d)

mol2/L•s

124.

How can milliliters (mL) be converted into liters (L)?

a)

multiply mL by 1000

b)

divide mL by 1000

c)

multiply mL by 100

d)

divide mL by 100

125.

According to this balanced equation, how many moles of Cu(NO3)3 are required to produce 24 mol of Al?

3Cu(s) + 2Al(NO3)3(aq) → 2Al(s) + 3Cu(NO3)2(aq)

a)

20

b)

36

c)

48

d)

60

126.

What is an isotope?

a)

two substances with the same molecular formula but different structures

b)

an atom of the same element but with a different number of neutrons so its mass is different

c)

similar elements in the same family

d)

substances that are the same colors

127.

What is a lone pair on an atom?

a)

a single electron

b)

a pair of protons

c)

a pair of electrons not bonded to another atom

d)

a pair of electrons bonded to only one other atom

128.

What is theoretical yield?

a)

the formulas for the products in a reaction

b)

amount of water mixed with the products

c)

the expected amount of product in grams that will form at the end of a reaction

d)

the limiting reactant

129.

What is the Law of Conservation of Mass?

a)

Mass of reactants stays the same

b)

Mass changes throughout a reaction

c)

Mass is created in a reaction to make new products

d)

The total mass of a system is always conserved

130.

What is a limiting reactant?

a)

The reactant that runs out and limits how much product you can make

b)

The reactant that stops reaction from starting

c)

The reactant that speeds up a chemical reaction

d)

The reactant that slows down a chemical reaction

131.

What does Calorimetry measure?

a)

amount of energy found in a substance measured by the amount of heat that is absorbed by water as the substance is burned

b)

amount of color stored in a substance that creates color you see

c)

the temperature that water changes when heated

d)

the amount of water needed to heat burning food

132.

How many valence electrons does oxygen have?

a)

2

b)

4

c)

6

d)

8