Which of the following statements about water is not true?
Water will hydrogen bond into highly ordered structures or "cages" around non-polar molecules.
The electron-rich oxygen atom of one water molecule can interact with an electron-poor hydrogen on another water molecule to form a hydrogen bond.
Water is a key player in the energetics of the hydrophobic effect.
In an ice crystal water molecules pack into open lattices consisting of five-membered oxygen rings.
At 25 degrees celsius liquid water is about 85% as hydrogen bonded as the water in ice, with each molecule in an average of 3.4 hydrogen bonds.
Which of the following is the best explanation for the hydrophobic effect?
It is caused by the attraction of hydrophobic groups for each other.
It is an entropic effect caused by the tendency of hydrophobic groups to increase their entropy by associating with other hydrophobic groups.
It is an entropic effect, caused by the tendency of water molecules to increase their entropy by excluding hydrophobic groups, which they must otherwise surround with highly ordered structures.
It is caused by the attraction of water for hydrophobic groups.
It is an entropic effect, caused by the tendency of water molecules to increase their entropy by forming highly ordered structures around the hydrophobic groups.
Which of the following statements about water is not true?
Water will hydrogen bond into highly ordered structures or "cages" around non-polar molecules.
The electron-rich oxygen atom of one water molecule can interact with an electron-poor hydrogen on another water molecule to form a hydrogen bond.
Water is a key player in the energetics of the hydrophobic effect.
In an ice crystal water molecules pack into open lattices consisting of five-membered oxygen rings.
At 25 degrees celsius liquid water is about 85% as hydrogen bonded as the water in ice, with each molecule in an average of 3.4 hydrogen bonds.
Which of the following is the best explanation for the hydrophobic effect?
| It is caused by the attraction of hydrophobic groups for each other. | ||
| It is an entropic effect caused by the tendency of hydrophobic groups to increase their entropy by associating with other hydrophobic groups. | ||
| It is an entropic effect, caused by the tendency of water molecules to increase their entropy by excluding hydrophobic groups, which they must otherwise surround with highly ordered structures. | ||
| It is caused by the attraction of water for hydrophobic groups. | ||
| It is an entropic effect, caused by the tendency of water molecules to increase their entropy by forming highly ordered structures around the hydrophobic groups. |
