Question 1

Which of the following substances has the highest boiling point according to the vapor pressure curves shown in the provided graph?

Accepted Answer

Ethylene glycol

Question 2

Based on the vapor pressure curves, which compound would evaporate most rapidly at room temperature (25°C)?

Accepted Answer

Diethyl ether

Question 3

If the atmospheric pressure is 760 mmHg, at what temperature does ethanol boil according to the graph?

Accepted Answer

78°C

Question 4

Which intermolecular force is primarily responsible for the high boiling point of ethylene glycol compared to diethyl ether?

Accepted Answer

Hydrogen bonding

Question 5

A sample of water is heated from 25°C to 100°C at 1 atm. Which phase change occurs at 100°C?

Accepted Answer

Boiling

Question 6

Given the vapor pressure curve for ethanol, what would happen to its boiling point if the external pressure is reduced to 600 mmHg?

Accepted Answer

The boiling point would decrease

Question 7

Which of the following best explains why diethyl ether is used as an anesthetic in medical procedures?

Accepted Answer

It has a high vapor pressure at room temperature, allowing it to vaporize easily

Question 8

If you mix ethanol and water, which intermolecular force will be present between the two molecules?

Accepted Answer

Hydrogen bonding

Question 9

Which equation can be used to relate the vapor pressure of a liquid to its temperature?

Accepted Answer

$$P_1$$/$$P_2$$ = \exp\left(\frac{\Delta H_{vap}}{R}\left(\frac{1}{$$T_2$$} - \frac{1}{$$T_1$$}\right)\right)$$

Question 10

A liquid has a normal boiling point of 78°C. What is its vapor pressure at 78°C?

Accepted Answer

1 atm

Question 11

Which of the following statements is true regarding the relationship between vapor pressure and boiling point?

Accepted Answer

A liquid boils when its vapor pressure equals the external pressure

Question 12

Which compound would be most suitable as an antifreeze agent based on the vapor pressure curves?

Accepted Answer

Ethylene glycol

Question 13

If the enthalpy of vaporization ($$\Delta H_{vap}) $$for water is 40.7 kJ/mol, which equation would you use to calculate the vapor pressure at a different temperature?

Accepted Answer

$$\ln\left(\frac{P_2$}{P_1$}\right) = -\frac{\Delta H_{vap}}{R}\left(\frac{1}{T_2$} - \frac{1}{T_1$}\right)$$

Question 14

Which of the following would increase the boiling point of water?

Accepted Answer

Adding a nonvolatile solute

Question 15

A solution of ethylene glycol in water is used in car radiators. What property of ethylene glycol makes it effective for this purpose?

Accepted Answer

It raises the boiling point and lowers the freezing point of water

Question 16

Which of the following best describes the effect of hydrogen bonding on the physical properties of water?

Accepted Answer

It increases the boiling point and decreases the vapor pressure

Question 17

If a liquid has a vapor pressure of 400 mmHg at 60°C, what will happen to its vapor pressure if the temperature is increased to 80°C?

Accepted Answer

It will increase

Question 18

Which of the following is NOT a colligative property?

Accepted Answer

Density

Question 19

A chemist wants to separate ethanol from water by distillation. Which property allows this separation?

Accepted Answer

Ethanol has a lower boiling point than water

Question 20

Which of the following best explains why vapor pressure increases with temperature?

Accepted Answer

More molecules have enough energy to escape the liquid phase

General Chemistry Practice Final Exam Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard