Deck 1: Molecular Reasons

Question 1

Thales believed that _____ is the principle element of all things.

A)earth
B)air
C)fire
D)water
E)gold

Answer 1

water

Question 2

The predecessor to chemistry is known as ____.

A)alchemy
B)pre-chemistry
C)biology
D)biochemistry
E)physical science

Answer 2

alchemy

Question 3

Which of these is the best definition of a scientific law?

A)A prediction based on a limited number of observations.
B)A method of explaining observations that appear contradictory.
C)A broadly applicable generalization with virtually no exceptions.
D)A method for approaching problems that is used by all scientists.
E)A rule made by scientists to ensure consistency in their observations.

Answer 3

A broadly applicable generalization with virtually no exceptions.

Question 4

Which two scientists are credited with the endorsement of a sun centered universe?

A)Dalton and Plato
B)Boyle and Copernicus
C)Copernicus and Galileo
D)Democritus and Vesalius
E)Copernicus and Vesalius

Question 5

Which of these statements is correct ?

A)The amount of carbon on earth is essentially constant.
B)The amount of carbon on earth fluctuates with the seasons.
C)The amount of carbon on earth is increasing due to plant and animal growth.
D)The amount of carbon on earth is decreasing due to consumption of carbon based fuels.
E)Both B and C are correct.

Question 6

The French chemist Antoine Lavoisier found that the weight of objects before burning and the weight of the products after burning were equal. He concluded that the total weight did not change during a process. Which of these best describes Lavoisier's conclusion?

A)From observation, Lavoisier created a scientific law.
B)From observation, Lavoisier created a scientific theory.
C)From scientific law, Lavoisier created a scientific theory.
D)From experimentation, Lavoisier created a scientific law.
E)From observation, Lavoisier created a scientific conclusion.

Question 7

A statement which summarizes the data obtained from a series of observations is known as a(n)____.

A)observation
B)law
C)theory
D)conclusion
E)experiment

Question 8

Which of these is the best definition of matter?

A)The pull of gravity on an object.
B)Anything that has weight and volume.
C)Anything that has mass and occupies space.
D)Anything that is directly proportional to weight.
E)The measure of the amount of space an object occupies.

Question 9

To explain natural phenomena scientists must _____.

A)have an opinion
B)make observations
C)guess correctly most of the time
D)agree with existing theories

Question 10

Which of these contributions did Alchemists of the Middle Ages make to modern science?

A)Sun centered universe and metallurgy
B)Metallurgy and development of scientific techniques
C)Scientific method and the Law of Conservation of Mass
D)Law of Conservation of Matter and The First Atomic Theory
E)Law of Conservation of Mass and the Law of Constant Composition

Question 11

Which of these statements about the scientific method is incorrect ?

A)It is a group of absolute truths.
B)It uses experiments that are reproducible
C)It is used for testing claims about the natural world.
D)It requires one to propose a theory and perform experiments to give results which confirm or disclaim the theory.
E)All of these are correct statements.

Question 12

Identify the entities which will correctly complete the flow chart.

A)I
B)II
C)III
D)IV
E)V

Question 13

Which scientist is incorrectly matched with his idea or theory?

A)I
B)II
C)III
D)IV
E)V

Question 14

A(n)____ is an explanation of a scientific observation.

A)law
B)theory
C)conclusion
D)prediction
E)epiphany

Question 15

Which of these is not part of the scientific method?

A)Observation
B)Law
C)Theory
D)Conclusion
E)Experiment

Question 16

Which of these is the best definition of a scientific theory?

A)A prediction based on a limited number of observations.
B)A method of explaining observations that appears contradictory.
C)A broadly applicable generalization with virtually no exceptions.
D)A method for approaching problems that is used by all scientists.
E)A tentative model that describes the underlying cause of a physical behavior.

Question 17

When using the scientific method, before experiments are done a ___________ should be established.

A)hypothesis
B)law
C)theory
D)conclusion

Question 18

Which scientist first theorized that matter was ultimately composed of small indivisible particles called atoms?

A)Dalton
B)Lavoisier
C)Empedocles
D)Plato
E)Democritus

Question 19

The scientific revolution of the 1500s was marked by a move away from ____ and towards ____ as a method for explaining the natural world.

A)law, theory
B)alchemy, research
C)reason, observation
D)scientific theory, experimentation
E)Both a and c are correct.

Question 20

Which of these is not a requirement of a scientifically acceptable theory?

A)Good predictive power of the theory
B)Proven by additional experimentation
C)Sound reasoning for a particular observation
D)Easily revised to accommodate new observations
E)Provides model of behavior consistent with other widely accepted theories

Question 21

Which of these substances are heterogeneous mixtures?
I. Steam
II. Milk of magnesia
III. Crude oil
IV. Rubbing alcohol"

A)II and III
B)I and IV
C)II, III, and IV
D)I, III, and IV
E)I, II, and III

Question 22

If 12.0 g of carbon react with 32.0 g of oxygen to form 44.0 g of carbon dioxide, which of these statements is false?

A)18.0 g of carbon will be needed to form 66.0 g of carbon dioxide.
B)48.0 g of oxygen will be needed to form 66.0 g of carbon dioxide.
C)48.0 g of carbon will be needed to form 132.0 g of carbon dioxide.
D)96.0 g of oxygen will be needed to form 132.0 g of carbon dioxide.
E)None of the above are false.

Question 23

A bowl of chocolate chip ice cream is best described as

A)a pure substance.
B)a homogenous mixture.
C)a heterogeneous mixture.
D)a compound which is a pure substance.
E)a chemical reaction between chocolate and vanilla ice cream.

Question 24

Which of these statements is true?

A)Solids are compressible and have variable shape.
B)Solids are incompressible and have variable shape.
C)Solids are compressible and have a fixed shape.
D)Solids are incompressible and have a fixed shape.

Question 25

Which of the following is true of ice when it melts to form liquid water? ​

A)A physical change occurs.
B)A chemical change occurs.
C)Both physical and chemical changes occur.
D)Neither a physical nor chemical change occurs.

Question 26

The smallest unit of a chemical compound is

A)an atom.
B)a molecule.
C)a nucleus.
D)an alpha particle.
E)None of the above are true.

Question 27

Carbon and oxygen react to form carbon dioxide. What mass of carbon dioxide is produced when 12.0 g of carbon react with 32.0 g of oxygen?

A)44 g
B)38 g
C)28 g
D)20 g
E)2.67 g

Question 28

Which of these statements is true?

A)The composition of both mixtures and pure substances is variable.
B)The composition of both mixtures and pure substances is fixed.
C)The composition of mixtures is variable and the composition of pure substances is fixed.
D)The composition of mixtures is fixed and the composition of pure substances is variable.
E)The composition of both mixtures and pure substances can be fixed or variable.

Question 29

A substance composed of two or more different elements in fixed proportions is known as a(n)____.

A)atom
B)element
C)molecule
D)Ion
E)compound

Question 30

A chocolate chip cookie is an example of what type of matter?

A)Element
B)Compound
C)Homogeneous mixture
D)Heterogeneous mixture
E)A cookie is not matter.

Question 31

Which of these substances are compounds?
I.Neon
II.Crude oil
III.Water
IV.Sodium chloride

A)I
B)I, and III
C)II, III, and IV
D)III and IV
E)II and IV

Question 32

The simplest form of substance is known as a(n)____.

A)element
B)ion
C)mixture
D)nucleus
E)homogeneous

Question 33

Which of these substances are mixtures?
I. Steam
II. Crude oil
III. Salt water
IV. Gun powder
V. Oxygen
VI. Mercury"

A)II and III
B)I and III
C)II, III, and IV
D)I, III, and V
E)II, III, IV, and VI

Question 34

What does the figure represent?
​

A)A heterogeneous mixture of elements.
B)A pure substance which is an element.
C)A pure substance which is a compound.
D)A homogenous mixture of elements and compounds.
E)A heterogeneous mixture of elements and compounds.

Question 35

Methane and oxygen react to form carbon dioxide and water. What mass of water is formed if 3.2 g of methane react with 12.8 g of oxygen to produce 8.8 g of carbon dioxide?

A)7.2 g
B)8.8 g
C)9.6 g
D)14.8 g
E)16.0 g

Question 36

Methane can be decomposed into two simpler substances, hydrogen and carbon. Therefore, methane

A)is a gas.
B)is an element.
C)is a mixture.
D)is a compound.
E)must have the formula CH.

Question 37

Which of the following is an example of a chemical change?

A)Glass breaking
B)Water freezing
C)Wood burning
D)Getting a haircut

Question 38

Which of the following statements does not describe a chemical compound?.

A)It contains two or more elements.
B)It is a pure substance.
C)It has a fixed composition.
D)It has a variable composition.
E)All of the statements are correct.

Question 39

Which of these statements is true ?

A)Gases are compressible and have variable shape.
B)Gases are incompressible and have variable shape.
C)Gases are compressible and have a fixed shape.
D)Gases are incompressible and have a fixed shape.

Question 40

What does the figure represent?
​

A)A heterogeneous mixture of elements.
B)A pure substance which is an element.
C)A pure substance which is a compound.
D)A homogenous mixture of elements and compounds.
E)A heterogeneous mixture of elements and compounds.

Question 41

A sample of heptane always contains 84% carbon and 16% hydrogen. Which of these best explains this phenomena?

A)Law of Constant Composition
B)Law of Conservation of Mass
C)Dalton's Atomic Theory
D)Law of Mass Action
E)Lavoisier's Law

Question 42

Which scientist is responsible for establishing the Law of Conservation of Mass?

A)Bohr
B)Proust
C)Dalton
D)Lavoisier
E)Galileo

Question 43

Analysis of a silicon dioxide (SiO₂)sample indicated it contained 46.75 g of silicon and 53.25 g of oxygen. Determine the mass of silicon in a sample of SiO₂ if the mass of oxygen is 21.3 g.

A)116.9 g
B)24.26
C)18.7 g
D)9.70 g
E)2.67 g

Question 44

Which of the following is a characteristic of the nucleus of an atom?

A)It is positively charged.
B)It accounts for most of the mass of the atom.
C)It accounts for most of the volume of the atom.
D)Both B + C are correct.
E)Both A + B are correct.

Question 45

Which of these statements best explains the law of constant composition?

A)All atoms of a given element have the same weight.
B)Atoms of different elements combine in fixed whole number ratios.
C)The weight of an object is neither created nor destroyed in a chemical reaction.
D)All samples of a given compound have the same proportion of constituent elements.
E)The sum of the masses of the reactants equals the sum of the masses of the products in a normal chemical reaction.

Question 46

Based on Rutherford's model of the atom, how many electrons would be found in an atom with 7 protons?

A)1
B)2
C)4
D)7
E)14

Question 47

Elements A and Z react to form compound AZ. Compound AZ contains 40% A and60% Z by mass. Which statement best explains the outcome when 100 g of A is mixed with 100 g of Z?

A)The reaction will form 200 g of AZ.
B)The reaction will form 100 g of AZ.
C)After all possible AZ is formed, some Z will be left over.
D)After all possible AZ is formed, some A will be left over.
E)No reaction will occur since the reactants are in the wrong ratio.

Question 48

Which law best illustrates the following statement? Regardless of the amount of fluorine available, 23 g of sodium always combines with 19 g of fluorine.

A)Law of Constant Composition
B)Law of Conservation of Mass
C)Dalton's Atomic Theory
D)Law of Mass Action
E)Lavoisier's Law

Question 49

Based on Rutherford's model of the atom, how many protons would be found in an atom with 17 electrons?

A)1
B)7
C)12
D)17
E)34

Question 50

Which of these statements is not correct according to Dalton's Atomic Theory?

A)Elements combine in fixed proportions to form compounds.
B)Atoms are converted into other atoms in a chemical reaction.
C)All matter is composed of small indivisible particles called atoms.
D)Atoms of one element are different from atoms of another element.
E)All of these statements are correct according to Dalton's Atomic Theory.

Question 51

Which of these statements is not consistent with Dalton's Atomic Theory?

A)All atoms of gold have the same chemical properties.
B)Electrons are equally distributed throughout an atom.
C)The properties of sodium are different from the properties of chlorine.
D)Compounds are formed when atoms combine in simple whole number ratios.
E)Atoms are rearranged in normal chemical reactions but are neither created nor destroyed.

Question 52

Analysis of a sodium chloride (NaCl)sample indicated that it contained 15 g of sodium and 23.1 g of chlorine. Determine the mass of chlorine in a sample of NaCl if the mass of sodium is 45.0 g.

A)29.2 g
B)60.0 g
C)68.1 g
D)69.3 g
E)83.1 g

Question 53

Which scientist is responsible for establishing the concept of a nuclear atom?

A)Rutherford
B)Proust
C)Dalton
D)Lavoisier
E)Galileo

Question 54

10.00 g of the chemical compound benzene (C₆H₆)contains 0.77 g of hydrogen and 9.23 g of carbon. What mass of benzene will contain 10.00 g of hydrogen?

A)129.9 g
B)0.77 g
C)92.3 g
D)77.0 g
E)None of these.

Question 55

Which of these sets of masses for nitrogen dioxide is not consistent with the others according to the Law of Constant Composition?

A)I
B)II
C)III
D)IV
E)V

Question 56

Which scientist is responsible for establishing the early atomic theory using the laws of Conservation of Mass and other related laws and observations?

A)Bohr
B)Proust
C)Dalton
D)Lavoisier
E)Galileo

Question 57

Which of these statements best explains the Law of Conservation of Mass?

A)All atoms of a given element have the same weight.
B)Atoms of different elements combine in fixed whole number ratios.
C)The weight of an object is neither created nor destroyed in a chemical reaction.
D)All samples of a given compound have the same proportion of constituent elements.
E)The sum of the masses of the reactants equals the sum of the masses of the products in any normal chemical reaction.

Question 58

Which of these statements is incorrect according to Rutherford's model of the atom?

A)Neutrons are part of the nucleus.
B)Most of the volume of an atom is empty space.
C)A neutral atom contains an equal number of protons and electrons.
D)An electron is located in close proximity to the nucleus of an atom.
E)The majority of the mass of the atom is concentrated in the nucleus.

Question 59

Which scientist is responsible for establishing the Law of Constant Composition?

A)Bohr
B)Proust
C)Dalton
D)Lavoisier
E)Galileo

Question 60

2.0 g of hydrogen react with 16.0 g of oxygen to form 18.0 g of water. If 3.0 g of hydrogen is reacted with 16.0 g of oxygen, which of the following is true?

A)18.0 g of water will form with 1.0 g of excess oxygen.
B)18.0 g of water will form with 1.0 g of excess hydrogen.
C)19.0 g of water will form.
D)17.0 g of water will form with 1.0 g of excess oxygen and 1.0 g of excess hydrogen.
E)None of the above is correct.

Question 61

Which scientist is incorrectly matched with his idea or theory?

A)I.
B)II.
C)III.
D)IV.
E)V.

Question 62

Which two subatomic particles compose the nucleus of an atom?

A)Protons, neutrons
B)Protons, electrons
C)Electrons, neutrons
D)Alpha particles, protons
E)Alpha particles, electrons

Question 63

Which scientist is incorrectly matched with his idea or theory?

A)I
B)II
C)III
D)IV
E)V

Question 64

Which of these subatomic particles is not found in nucleus of an atom?

A)Proton
B)Neutron
C)Electron
D)Both A and B
E)None of these

Question 65

A college freshman reports to Student Health Services on campus complaining of a soar throat and fever. The doctor swabs the back of the student's throat and begins a throat culture. The swabbing and growing of a culture is an example of what step in the scientific method?

A)law
B)Theory
C)Conclusion
D)Observation
E)Experimentation

Question 66

Which of these statements about science is incorrect ?

A)Science influences culture and society.
B)Science reveals knowledge not attainable by other means.
C)Science is a fundamental way to understand the world around us.
D)Decisions involving scientific principles are often made by nonscientists.
E)All of these are correct statements.