Question 1

A solution that is 1 ppm contains more dissolved solute than one that is 1 ppt.

Accepted Answer

1 ppm (part per million) is a smaller concentration than 1 ppt (part per thousand), meaning 1 ppt contains more dissolved solute.

Question 2

The solubility of KBr at 20°C is 60 g/100 g H₂O.Increasing the pressure above the solution will significantly increase the solubility of KBr.

Accepted Answer

The solubility of solid solutes like KBr in liquid solvents is not significantly affected by changes in pressure, unlike the solubility of gases in liquids.

Question 3

An aqueous solution containing a nonvolatile solute such as NaCl will have a freezing point above 0°C at 1 atm pressure.

Accepted Answer

The presence of a nonvolatile solute like NaCl in water lowers the freezing point of the solution below 0°C at 1 atm pressure due to the colligative property of freezing point depression.

Question 4

Colligative properties depend only on the concentration of solute particles,not on their identity.

Accepted Answer

Colligative properties, such as boiling point elevation, freezing point depression, vapor pressure lowering, and osmotic pressure, depend solely on the number of solute particles in a solution and not on the chemical identity of the solute particles.

Question 5

The solubility of gases in liquids increases with increasing pressure.

Accepted Answer

According to Henry's Law, the solubility of a gas in a liquid is directly proportional to the pressure of the gas above the liquid. Therefore, as pressure increases, the solubility of the gas in the liquid also increases.

Question 6

An aqueous solution containing a nonvolatile solute such as sucrose will boil above 100°C at 1 atm pressure.

Accepted Answer

The presence of a nonvolatile solute, like sucrose, in water causes a colligative property known as boiling point elevation, which means the solution will boil at a higher temperature than the pure solvent at the same pressure.

Question 7

Osmosis is the process that regulates the sodium/potassium ratio in living cells.

Accepted Answer

Osmosis is the movement of water across a semipermeable membrane from an area of low solute concentration to an area of high solute concentration. The regulation of sodium/potassium ratios in cells is primarily achieved through active transport mechanisms, notably the sodium-potassium pump (Na+/K+-ATPase), not osmosis.

Question 8

Osmosis may be defined as the movement of a solvent through a semipermeable membrane from a region of higher solute concentration to one of lower solute concentration.

Accepted Answer

Osmosis is the movement of a solvent through a semipermeable membrane from a region of lower solute concentration to one of higher solute concentration.

Question 9

The heavier the solute molecule is,the greater its effect on the freezing point depression of a solution.

Accepted Answer

The effect of a solute on the freezing point depression of a solution is dependent on the number of particles (i.e., the molal concentration) in solution, not the mass of the solute molecules.

Quiz 6: Solutions