Johnson The Chemistry Of Life Test Bank Docx Ch.2

Essentials of The Living World, 6e (Johnson)

Chapter 2 The Chemistry of Life

1) The nucleus of an atom is composed of

A) protons and neutrons.

B) protons and electrons.

C) only electrons.

D) only protons.

E) only neutrons.

2) Atoms that have a positive or negative charge are known as

A) magnetic.

B) electrically neutral.

C) ions.

D) protons.

E) stable.

3) The chemical behavior of an atom is determined by its

A) protons.

B) neutrons.

C) nuclei.

D) electrons.

E) mass.

4) In a neutral atom, the number of protons is always

A) equal to the electrons.

B) more than the electrons.

C) more than the neutrons.

D) less than the neutrons.

E) less than the electrons.

5) The volume of space around a nucleus where an electron is most likely to be located is called the ________ of that electron.

A) parameter

B) spin

C) pathway

D) orbital

E) nucleus

6) Electrons possess energy of position, also known as ________ energy.

A) kinetic

B) latent

C) potential

D) opposition

E) excitable

7) Most elements in nature exist as mixtures of

A) unreactive atoms.

B) different isotopes.

C) gases.

D) liquids.

E) stable ions.

8) Carbon-14 is

A) an important ion used in chemical reactions.

B) the most common form of carbon.

C) an isotope used in dating fossils.

D) widely used in hydrogen bonds.

E) All of the answer choices are correct.

9) When an electron is transferred from one atom to another, the two atoms will then be electrically attracted to one another. This results in the formation of a(n) ________ bond.

A) hydrogen

B) covalent

C) kinetic

D) ionic

E) static

10) What type of bond forms between two atoms sharing electrons?

A) hydrogen

B) covalent

C) kinetic

D) ionic

E) static

11) Water molecular bond to each other via hydrogen bonds. These bonds form between the slight negative charge of ________, and the slight positive charge of ________, on adjacent water molecules.

A) oxygen; hydrogen

B) hydrogen; carbon

C) hydrogen; oxygen

D) oxygen; carbon

E) hydrogen; nitrogen

12) A solution with a pH of 4 has ________ times the concentration of H+ present compared to a solution with a pH of 5.

A) 10

B) 100

C) 2

D) 1,000

E) 200

13) The mass number of an atom is the number of

A) neutrons only.

B) electrons plus the number of protons.

C) protons only.

D) protons plus the number of neutrons.

E) electrons, plus the number of neutrons, plus the number of protons.

14) The atomic number of an atom is the number of

A) neutrons only.

B) electrons plus the number of protons.

C) protons only.

D) protons plus the number of neutrons.

E) electrons, plus the number of neutrons, plus the number of protons.

15) The first shell in any atom contains one orbital which may contain as many as

A) 2 electrons.

B) 8 protons.

C) 8 electrons.

D) 4 neutrons.

E) 2 neutrons.

16) The second shell in an atom contains ________ orbitals and holds up to ________ electrons.

A) 4; 4

B) 3; 2

C) 4; 8

D) 3; 8

E) 8; 24

17) If an element has an atomic number of 6 and a mass number of 14, how many neutrons does it have?

A) 6

B) 14

C) 7

D) 8

E) 28

18) If you were grading an exam about water, which statement would lose points?

A) Hydrogens have partial negative charges.

B) Water is a polar molecule.

C) Covalent bonds exist within a water molecule.

D) Hydrogen bonds exist between water molecules.

E) Hydrogen bonds are relatively weak bonds.

19) Which type of chemical substance lowers the H+ concentration in a solution?

A) ice

B) acid

C) base

D) buffer

E) hydrogen ion

20) Water moving up into a paper towel, a polar substance, is attributable to

A) heat storage.

B) high heat of vaporization.

C) electronegativity.

D) cohesion.

E) adhesion.

21) If you wanted to stop an insect from walking on water, you would need to add something to the water to stop

A) high heat of vaporization.

B) cohesion.

C) adhesion.

D) polar covalent bonds.

E) heat storage.

22) Buffers always release H+ ions into solution to stabilize pH.

23) Nonpolar molecules, such as fats, are water-soluble.

24) The number of protons in the nucleus of an atom is called the ________ ________.

25) If you wanted to change the mass number of an atom, you would have to alter either the number of protons or the number of ________.

26) If you were helping a professor with an experiment in which different forms of carbon were to be used, you would go to the chemical cabinet to find different ________.

27) When water ionizes, the negatively charged OH fragment is the ________ ion.

28) We use the ________ scale to measure concentrations of hydrogen ions in a solution.

29) A solution with a pH of 3 is said to be highly ________.

30) The chemical bond within a water molecule is a ________ bond.

31) Due to ________ bonding, ice is less dense than water.

32) A substance that increases the concentration of H+ is a(n) ________.

33) While exercising you begin to sweat. Sweating is cooling your body because it takes energy with it in the form of heat.

34) Two hydrophobic molecules in a cell membrane would form a hydrogen bond.

35) You are chemically analyzing a new compound. It does not dissolve in water. You characterize it as being hydrophilic.

36) Doctors prescribe medicines to help the symptoms of acid reflux which cause burning in the esophagus from excess acid in the stomach. To help neutralize the acid, medicines are used to

A) accept excess H+.

B) accept excess OH-.

C) donate excess H+.

D) donate excess OH-.

E) donate either OH- or H+.

37) In an ionic bond, a cation is an atom that has ________ and is now positively charged.

A) lost an electron

B) gained an electron

C) lost a neutron

D) gained a neutron

E) gained a proton

38) Covalent bonds between water molecules require a high amount of energy to break which is why water heats slowly.

39) Ionic bond of salt molecules form between negative sodium molecules and positive chlorine atoms resulting in a crystal formation.