Which of the following best explains how hydrogen bonding affects the heat of vaporization for water?
a. the hydrogen bonds cause water to resist a change in temperature.
b. the number of hydrogen bonds in water increases the amount of h+ ions available.
c. the uneven pull of hydrogen bonds causes water molecules to repel each other.
d. the hydrogen bonds cause water to be highly attracted to other substances.

A. The hydrogen bonds cause water to resist a change in temperature.

Explanation:

Heat of vaporization is defined as the amount of heat required to convert 1 mole of liquid to gaseous state.

Water has high heat of vaporization due to the presence of strong hydrogen bonds between  hydrogen and a electronegative element oxygen. As the water molecules are strongly bonded to each other, large amount of heat is required to raise the temperature of water.

The molecules will not be able to gain enough kinetic energy and thus temperature changes slowly.

step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.