Deck 2: Chemistry of Life

Question 1

Which subatomic particle has a positive charge?

A) electron
B) neutron
C) photon
D) neutrino
E) proton

Answer 1

E

Question 2

An element's mass number is equal to the sum of its

A) protons and electrons.
B) protons and neutrons.
C) electrons and neutrons.
D) protons only.
E) electrons only.

Answer 2

B

Question 3

The nucleus of an atom contains

A) neutrons and protons.
B) neutrons and electrons.
C) protons and electrons.
D) protons only.
E) neutrons only.

Answer 3

A

Question 4

The time it takes for half of a quantity of a radioisotope to decay into a more stable isotope is

A) the same for all elements.
B) decay time.
C) half-life.
D) disintegration time.
E) dependent on temperature.

Question 5

The atomic number refers to the

A) mass of an atom.
B) number of protons in an atom.
C) number of both protons and neutrons in an atom.
D) number of neutrons in an atom.
E) number of electrons in an atom.

Question 6

All atoms of an element have the same number of

A) ions.
B) protons.
C) neutrons.
D) electrons.
E) protons and neutrons.

Question 7

Which is the smallest portion of a substance that retains the properties of an element?

A) atom
B) compound
C) ion
D) molecule
E) mixture

Question 8

Isotopes

A) are identical in mass number to the "standard" element.
B) contain a different number of electrons than the "standard" element.
C) contain a different number of protons than the "standard" element.
D) contain the same number of protons but a different number of neutrons than the "standard" element.
E) are actually a different element than the "standard" element.

Question 9

Which element does not contain a neutron in its nucleus?

A) helium
B) carbon
C) oxygen
D) hydrogen
E) nitrogen

Question 10

Which two subatomic particles are almost always equal in number?

A) electrons and neutrons
B) protons and neutrons
C) protons and electrons
D) photons and electrons
E) neutrons and neutrinos

Question 11

Radioisotopes

A) are unstable and emit energy and particles to stabilize themselves.
B) are different elements from the "standard" elements.
C) are very stable and do not change over time.
D) contain more electrons than the "standard" element.
E) contain less electrons than the "standard" element.

Question 12

The neutral subatomic particle is (are) the

A) neutron.
B) proton.
C) electron.
D) neutron and proton.
E) proton and electron.

Question 13

The negative subatomic particle is (are) the

A) neutron.
B) proton.
C) electron.
D) neutron and proton.
E) proton and electron.

Question 14

Organisms consist mostly of four elements. They are carbon, hydrogen, oxygen, and

A) iron.
B) chlorine.
C) silicon.
D) nitrogen.
E) phosphorous.

Question 15

A sugar or other molecule in which radioisotopes have been substituted for some atoms is a(n)

A) enzyme.
B) reactant.
C) tracer.
D) subatomic particle.
E) quark.

Question 16

How many natural elements exist on Earth?

A) 100
B) 112
C) 88
D) 96
E) 110

Question 17

An element that represents less than 0.01 percent of body weight is known as a(n)

A) compound.
B) trace element.
C) molecule.
D) isotope.
E) analog.

Question 18

Transmutation of an element (the change of an element into a different element) occurs due to

A) exposure to strong sunlight.
B) exposure to certain chemicals.
C) natural aging of the element.
D) combining with another element.
E) radioactive decay.

Question 19

Positron Emission Tomography utilizes ____ to yield results of a scan.

A) tracers
B) x-rays
C) neutrinos
D) photons
E) mesons

Question 20

Examples of isotopes include:

A) oxygen 8 and oxygen 16.
B) carbon 12 and nitrogen 14.
C) hydrogen 1 and helium 1.
D) sodium 23 and potassium 23.
E) carbon 12 and carbon 14.

Question 21

The bonding of two or more atoms creates a(n)

A) ion.
B) molecule.
C) mixture.
D) suspension.
E) particle.

Question 22

Which of the following is NOT an element?

A) water
B) oxygen
C) carbon
D) chlorine
E) hydrogen

Question 23

Water is an example of a(n)

A) atom.
B) ion.
C) compound.
D) mixture.
E) element.

Question 24

Choose the correct formula for the reaction that takes place between hydrogen and oxygen to produce water.

A) H₂ + O₂ → H₂O
B) H + O → H₂O
C) 2H₂ + O₂ → 2H₂O
D) 2H₂O + O₂ → 4H₂O
E) 2H₂ + 2O₂ → 2H₂O

Question 25

Which of the following is NOT a compound?

A) salt
B) sugar
C) carbon
D) oxygen gas
E) water

Question 26

Electrons inside a shell travel in

A) straight paths.
B) orbitals
C) zigzag patterns
D) two dimensions
E) one dimension

Question 27

When two or more molecules simply mingle, a(n) ____ is created.

A) compound
B) mixture
C) molecule
D) ionic compound
E) suspension

Question 28

Electrons move around the atomic nucleus in

A) zigzag patterns.
B) straight paths.
C) shells.
D) two dimensions.
E) one dimension.

Question 29

Which of the following is not one of the four most abundant elements in the body?

A) carbon
B) hydrogen
C) oxygen
D) nitrogen
E) calcium

Question 30

Atoms without vacancies are considered to be

A) ions.
B) negatively charged.
C) positively charged.
D) inert.
E) highly active.

Question 31

An atom that is considered inert is

A) oxygen.
B) hydrogen.
C) nitrogen.
D) carbon.
E) helium.

Question 32

PET (positron-emission tomography) scans use radioisotopes attached to what substances to detect abnormalities?

A) other radioisotopes
B) subatomic particles
C) carbon atoms
D) glucose or other biological molecules
E) plutonium

Question 33

A tracer is a substance with what attached to it?

A) water
B) carbon
C) a radioisotope
D) an ion
E) a positron

Question 34

Which of the following answers include all the others?

A) atoms
B) molecules
C) electrons
D) elements
E) protons

Question 35

The maximum number of electrons in a shell is

A) two.
B) four.
C) six.
D) eight.
E) ten.

Question 36

The time it takes for half of a quantity of a radioisotope to decay into a more stable isotope is

A) the same for all elements.
B) decay time.
C) half-life.
D) disintegration time.
E) dependent on temperature.

Question 37

When an atom's outer shell is filled it is

A) unstable.
B) an ion.
C) most stable.
D) polarized.
E) negatively charged.

Question 38

A(n) ____ consists of two or more bonded elements in proportions that never vary.

A) ion
B) mixture
C) compound
D) network solid
E) satisfied orbital

Question 39

The element in the body with the greatest number of atoms is

A) phosphorus.
B) oxygen.
C) hydrogen.
D) calcium.
E) carbon.

Question 40

A union between the electron structures of atoms is a(n)

A) chemical bond.
B) hydrogen bond.
C) isotopic bond.
D) physical bond.
E) atomic bond.

Question 41

Which type of bond holds the two strands of DNA together?

A) ionic
B) network
C) polar covalent
D) hydrogen
E) non-polar covalent

Question 42

Which type of bond makes water liquid?

A) ionic
B) covalent
C) polar covalent
D) nonpolar covalent
E) hydrogen

Question 43

Molecular hydrogen is an example of which type of molecule?

A) polar covalent
B) nonpolar covalent
C) ionic
D) coordinate covalent
E) network

Question 44

Why does water have a high heat capacity?

A) because it has covalent bonds
B) because it has ionic bonds
C) because it has hydrogen bonds
D) because it has a high boiling point
E) because it has a low freezing point

Question 45

A hydrogen bond is

A) a sharing of a pair of electrons between a hydrogen and an oxygen nucleus.
B) a sharing of a pair of electrons between a hydrogen nucleus and either an oxygen or a nitrogen nucleus.
C) an attractive force that involves a hydrogen atom and an oxygen or a nitrogen atom that are either in two different molecules or within the same molecule.
D) found only in water molecules.
E) is the strongest form of chemical bond.

Question 46

The bond formed when atoms share electrons is a(n) ____ bond.

A) hydrogen
B) ionic
C) covalent
D) crystalline
E) network

Question 47

In a polar covalent bond, the atoms of the different elements do not share electrons equally because

A) one is a metal and one is a non-metal.
B) both are metals.
C) both are non-metals.
D) one element has more neutrons.
E) one element has more protons.

Question 48

A free radical will "steal" what particle from a stable molecule?

A) a proton
B) a neutron
C) an atom
D) an electron
E) a positron

Question 49

A bond that joins atoms that have opposite charges is a(n)

A) covalent bond.
B) hydrogen bond.
C) ionic bond.
D) coordinate covalent bond.
E) polar covalent bond.

Question 50

The process in which an atom or molecule loses one or more electrons to another atom or molecule is called

A) reduction.
B) dehydration.
C) oxidation.
D) condensation.
E) hydrolysis.

Question 51

Water stabilizes body temperature and dissolves many substances because

A) it evaporates easily.
B) its molecules are covalent.
C) its molecules are ionic.
D) it contains hydrogen bonds.
E) it is free of minerals.

Question 52

How do hydrophobic molecules interact with water?

A) attracted to
B) absorbed by
C) repelled by
D) mixed with
E) polarized bond

Question 53

What is formed when an atom loses or gains an electron?

A) a molecule
B) an ion
C) a compound
D) a mixture
E) a solvent

Question 54

Generally, an atom carries no charge because it has as many electrons as

A) neutrons.
B) orbitals.
C) shells.
D) protons.
E) neutrinos.

Question 55

A water molecule is an example of which type of molecule?

A) polar covalent
B) nonpolar covalent
C) ionic
D) coordinate covalent
E) network

Question 56

The many oxidation reactions that take place in our bodies cause the formation of

A) free radicals.
B) antioxidants.
C) covalent molecules.
D) ionic molecules.
E) hydrogen bonds.

Question 57

A salt will dissolve in water to form

A) acids.
B) gases.
C) ions.
D) bases.
E) polar solvents.

Question 58

What makes water a solvent?

A) Fats dissolve in it.
B) Ions and polar molecules dissolve in it.
C) It mixes well with alcohol.
D) It evaporates easily.
E) It contains no minerals.

Question 59

A molecule is

A) a combination of two or more atoms.
B) less stable than its constituent atoms separated.
C) electrically charged.
D) a carrier of one or more extra neutrons.
E) one atom.

Question 60

The bond in table salt (NaCl) is

A) polar.
B) ionic.
C) covalent.
D) double.
E) nonpolar.

Question 61

H₂CO₃ is

A) sulfuric acid.
B) carbonic acid.
C) carbolic acid.
D) hydrochloric acid.
E) nitric acid.

Question 62

A reaction of a strong acid and a strong base will produce water and

A) a buffer.
B) a salt.
C) gas.
D) solid precipitate.
E) solute.

Question 63

What substances will release hydrogen ions when their concentration is low and accept them when their concentration is high?

A) salts
B) acids
C) bases
D) buffers
E) alkalines

Question 64

If a molecule contains carbon and at least one atom of hydrogen, it is referred to as being

A) inorganic.
B) acidic.
C) basic.
D) organic.
E) crystalline.

Question 65

Substances that give up an electron to a free radical are called

A) reducing agents.
B) oxidizing agents.
C) neutralizing agents.
D) antibiotics.
E) antioxidants.

Question 66

Which element makes up more than half of the human body?

A) calcium
B) hydrogen
C) oxygen
D) carbon
E) nitrogen

Question 67

A buffer system

A) makes new hydrogen ions.
B) eliminates hydrogen ions already present.
C) binds carbon ions.
D) releases hydrogen ions.
E) produce excess acid.

Question 68

Smoke from fossil fuels, motor vehicle exhaust, and nitrogen fertilizers can lead to

A) greater cloud formation.
B) acid rain.
C) basic rain.
D) rain with high mineral content.
E) salted rain.

Question 69

Proteins that speed up reactions are known as

A) salts.
B) buffers.
C) monomers.
D) polymers.
E) enzymes.

Question 70

HCl in the stomach acts to

A) neutralize buffers.
B) kill harmful bacteria.
C) switch off certain digestive enzymes.
D) produce trypsin.
E) prevent breakdown of protein.

Question 71

Fluid inside most human cells is about

A) pH 7.
B) pH 9.
C) pH 4.
D) pH 11.
E) pH 2.

Question 72

Natural sources of antioxidants do not include

A) vitamin C.
B) vitamin E.
C) orange vegetables.
D) green leafy vegetables.
E) O₂^-.

Question 73

A pH of 10 is how many times as basic as a pH of 7?

A) 2
B) 3
C) 10
D) 100
E) 1000

Question 74

Cellular pH is kept near a value of 7 because of

A) salts.
B) buffers.
C) acids.
D) bases.
E) water.

Question 75

A buildup of H₂CO₃ in the blood will lead to

A) alkalosis.
B) calcium buildup.
C) acidosis.
D) hydroxide ion increase.
E) HCO₃ ^- increase.

Question 76

Antioxidant-rich foods are typically

A) low in fat and high in fiber.
B) high in fat and low in fiber.
C) high in sugars and low in fat.
D) high in fiber and high in fat.
E) low in sugars and high in fiber.

Question 77

Each carbon atom can share pairs of electrons with as many as ____ other atoms.

A) 2
B) 3
C) 4
D) 5
E) 6

Question 78

The pH scale measures the

A) hydroxide ion concentration.
B) concentration of a water-based solution.
C) hydrogen ion concentration.
D) number of water molecules in a solution.
E) concentration of dissolved solute.

Question 79

Atoms or clusters of atoms that are covalently bonded to carbon and influence the behavior of organic compounds are known as

A) functional groups.
B) ions.
C) acids.
D) network solids.
E) anhydrides.

Question 80

Which of the following would NOT be used in connection with the word acid ?

A) excess hydrogen ions
B) contents of the stomach
C) magnesium hydroxide
D) pH less than 7
E) HCl