1. Which of the following is the essential characteristic of a polar molecule?
a) contains double or triple bonds
b) is formed at extremely low temperatures
c) contains ions as part of the structure
d) has an asymmetrical distribution of electrical charge
e) contains the element oxygen
2. Isomers are molecules that
a) react readily with one another
b) have the same molecular formula
c) have different molecular masses
d) differ in the number of unsaturated bonds
e) must contain the same functional group
3. In living organisms, buffers do which of the following?
a) prevent charged particles from entering cells
b) neutralize the effect of enzymes
c) maintain pH in the cells within a narrow range, allowing enzymes to function
d) allow the pH of cells to change without affecting the action of the enzymes
e) maintain cytoplasm in a fluid condition
4. When atoms from two different elements are brought together under conditions that will favour a reaction and they have similar electronegativities, which type of chemical bond is most likely to form?
a) nonpolar covalent bond
b) polar covalent bond
c) ionic bond
d) London forces
e) hydrogen bond
5. How many electrons are involved in each covalent bond?
a) 1
b) 2
c) 4
d) 6
e) 8
6. An amino acid always has an amino group, as its name suggests. What other group is also present in all amino acids?
a) a methyl group
b) a carboxyl group
c) an aldehyde group
d) a hydroxyl group
e) a carbonyl group
7. The following structural formula is representative of which functional group?
a) sulfhydryl
b) carboxyl
c) hydroxyl
d) amino
e) carbonyl
8. The following structural formula is representative of which functional group?
a) Sulfhydryl
b) carbonyl
c) hydroxyl
d) amino
e) carboxyl
9. In terms of maintaining the shape of an enzyme, the strongest bonds involved are
a) covalent (disulfide) bonds
b)