Water, pH and Macromolecules
Polyprotic acids such as H3PO4, can act as acid-base buffers

at pH values around any of their pKa's
only in combination with polyprotic bases
at pH values around neutrality
if their concentration is kept low

ANSWER DOWNLOAD EXAMIANS APP

Water, pH and Macromolecules
Which of the following character does not apply to water?

The water molecule is asymmetric
The water molecule readily forms hydrophobic interactions
All three atoms in the water molecule readily form hydrogen bonds
The covalent bonds in water are highly polarized

ANSWER DOWNLOAD EXAMIANS APP

Water, pH and Macromolecules
Which of the following statements about water is correct?

Nonpolar substances like oils are not soluble in it
All of these
It is critical for many of the chemical processes found in living systems
Polar substances that can form hydrogen bonds will dissolve in it

ANSWER DOWNLOAD EXAMIANS APP

Water, pH and Macromolecules
Which of the following statements about covalently bonded molecules is false?

Such molecules often result from the interaction of ionized atoms
The chemical bonds that hold the molecule together are relatively strong
Electrons are shared between the atoms that make up the molecule
Noncovalent bonds may also be present, especially if the molecule is large

ANSWER DOWNLOAD EXAMIANS APP