CHAPTER 2, CHEMISTRY QUIZ

_____1. Which of the following elements is Not one of the six most common in living organisms?
a) carbon    b) oxygen    c) iron    d) nitrogen    e) hydrogen

_____2. The are ___ naturally occurring elements.
a) 57    b) 108    c) 95    d) 92    e) 87

_____3. Which statement is Not true about elements?
a) An element cannot be broken down into substances with different properties.
b) An element consists of atoms and molecules.
c) There is only one kind of atom in each type of element.
d) All atoms of an element contain the same number of protons.
e) Atoms of an element may contain different numbers of neutrons.

_____4. Which term is based on the Greek root word for "uncut" or "indivisible"?
a) atom    b) element    c) molecule    d) chemical    e) electron

_____5. Which statement is Not true about subatomic particles?
a) Protons are found in the nucleus.
b) Neutrons have no electrical charge.
c) Electrons contain much less mass than neutrons.
d) Electrons are found in orbitals around the nucleus.
e) All electrons in an atom contain the same amount of energy.

_____6. Which is Not true about the electrical charges in chemistry?
a) Protons carry a positive charge.
b) In an atom, the number of protons and neutrons must be equal.
c) An atom is neutral when the positive and negative charges balance.
d) An ion contains one or more positive or negative charges.

_____7. An atom's atomic number is best described as the number of
a) protons it contains
b) neutrons it contains
c) electrons in the outermost shell
d) protons and neutrons it contains
e) protons and electrons it contains

_____8. An atom's atomic mass is best described as the mass of
a) protons it contains
b) neutrons it contains
c) electrons in the outermost shell
d) protons and neutrons it contains
e) protons and electrons it contains

_____9. The characteristic way in which atoms of an element react is most related to the
a) number of electrons in the outermost shell
b) number of electrons in the innermost shell
c) number of neutrons in the outermost shell
d) number of neutrons in the nucleus
e) size of the nucleus

_____10. Potential energy is best described as the
a) ability to do work
b) energy of motion of molecules
c) energy that comes from the sun
d) energy in the nucleus of an atom
e) stored energy that is available to do work

_____11. Which of the following statements is Not true about electron configurations?
a) If an atom has only one shell, it is complete with two electrons.
b) If an atom has two or more shells, the octet rule applies.
c) If an atom has two on more shells, the outer shell is complete with eight electrons.
d) Atoms with more than eight electrons in the outer shell react by gaining electrons.
e) Atoms with eight electrons in the outer shell are not reactive at all.

_____12. An orbital is best described as
a) the electron shell closest to the nucleus.
b) the outermost electron shell of an atom.
c) the volume of space in which electrons are most often found.
d) the original energy level of electrons in photosynthesis.

_____13. Which statement does Not describe a chemical equation?
a) The products are placed to the left of the arrow.
b) The reactants are placed to the left of the arrow.
c) The arrow represents the direction in which the reaction proceeds.
d) Atoms must be balanced on both sides of the arrow.

_____14. Which statement is Not true about ionic bonds?
a) One atom acts as an electron donor and another acts as an electron acceptor.
b) Electrons are completely lost or gained in ion formation.
c) An ion has the same number of electrons as a nonionic atom of the same element.
d) An ionic reaction occurs between positive and negative ions.
e) A salt such as NaCl is formed by an ionic reaction.

_____15. Which statement is Not true about covalent bonds?
a) Covalent bonds form when an electron is completely lost or gained from an atom.
b) A covalent molecule contains one or more covalent bonds.
c) A single covalent bond is drawn as a line between two atoms.
d) A pair of electrons is shared between two atoms for each covalent bond.
e) Shared electrons allow an atom to complete its outer electron shell in a covalent molecule.

_____16. Which statement is Not true about polar covalent bonds?
a) Most covalent bonds are nonpolar, with electrons shared fairly equally between the atoms.
b) Polar covalent bonds are important in the characteristics of water.
c) Electrons are shared unequally in a polar covalent bond.
d) The large atom in a polar bond attracts the electron more strongly than the smaller atom.
e) The oxygen of a water molecule is electropositive relative to the hydrogen.

_____17. Which statement is Not true about water's properties?
a) Water molecules are cohesive, able to cling to each other.
b) Water molecules are adhesive, able to wet substances other than water.
c) Water is a universal solvent due to its polar nature.
d) The temperature of water rises and falls quickly.
e) Ice is less dense than water and floats on its surface.

_____18. Which term is based on the Greek root word for "water" and "fear"?
a) hydrostatic    b) homeostatic    c) hydrophobic    d) hydrophilic    e) hyperphobic

_____19. What happens when water ionizes?
a) Equal amounts of hydrogen and hydroxyl ions are formed.
b) Ions are irreversibly formed.
c) Many ions are produced,
d) Anything in solution in water becomes ionized.
e) The water changes its pH because of the ions.

_____20. Which statement is Not true about the pH scale?
a) The scale indicates the relative concentrations of hydrogen and hydroxyl ions in a solution.
b) The scale ranges from 1 to 15.
c) pH 7 has a balanced level of H+ and OH-.
d) Anything below pH 7 is acidic and above pH 7 is basic.
e) A change of one pH unit represents a ten-fold increase or decrease in hydroxyl ion concentration.

_____21. If the pH of cytoplasm is approximately 7.2, the cytoplasm is
a) very acidic    b) slightly acidic    c) precisely neutral    d) slightly alkaline    e) very alkaline

_____22. An atom, such as calcium, which has two electrons in the outer shell, would most likely
a) share to acquire a complete outer shell.
b) lose these two electrons and become a negatively charged ion.
c) lose these two electrons and become a positively charged ion.
d) bind with carbon by way of hydrogen bonds.
e) bind with another calcium to satisfy its energy needs.

_____23. In which of these are the electrons shared unequally?
a) double covalent bond
b) triple covalent bond
c) hydrogen bond
d) polar covalent bond
e) ionic and covalent bonds

_____24. Acids
a) release hydrogen ions.                                          c) have a pH value above 7.
b) take up hydroxide ions and become neutral.         d) increase the number of water molecules.

_____25. A pH of 10 is how many more times basic than a pH of 7?
a) 2     b) 10    c) 100    d) 1000    e) 10,000

_____26. A solution that has a concentration of H+ that is 10,000 times lower than a solution
with a pH of 6, itself has a pH of
a) 2     b) 3     c) 4      d) 10       e) 11

_____27. A solution with pH of 4 has how many more hydrogen ions than one with a pH of 8?
a) 320      b) 4,000    c) 10,000      d) 1/4,000      e) 1/10,000

_____28. Which of the following bond types is the strongest?
a) ionic    b) covalent    c) Van der Waals    d) hydrophobic      e) hydrogen

_____29. The polarity of the water molecule causes it to be attracted to other polar molecules.
This property is referred to as
a) adhesion     b) cohesion     c) surface tension      d) specific heat      e) hydrogen bonding

_____30. During a chemical reaction, the loss of an electron from an atom or molecule is termed
a) reduction    b) cellular respiration      c) kinetics     d) oxidation      e) metabolism

_____31. Which of the following best explains surface tension?
a) Hydrogen of one water molecule are attracted to the hydrogens of another water molecule.
b) Oxygen of one molecule is attracted to hydrogens of the same molecule.
c) Hydrogen of one water molecule is attracted to the oxygen of another water molecule.
d) Water molecules increase the buoyancy of each other.
e) Water molecules have a high heat of evaporation.

_____32. Water can move from the roots of the trees to their uppermost branches, and basilisk lizards can run
on water for brief periods of time because of surface tension. Surface tension is the property of water caused by
a) attraction of a hydrogen atom of one water molecule to the oxygen of another water molecule.
b) attraction of an oxygen molecule of water to one or more hydrogen atoms of another water molecule.
c) short lived hydrogen bonds between water molecules.
d) cohesion
e) All of the above.