Q: Calculate the amount of heat (in joules) required to raise the temperature of 150 g of water from 20.0°C to 80.0°C. (Specific heat of water $$c = 4.18 \ \mathrm{J/g\cdot K})$$

$$q = 150 \times 4.18 \times (80.0 - 20.0) = 37,620 \ \mathrm{J}$$

Q: A brass candlestick (mass = 0.59 kg) cools from 98.0°C to 6.8°C, releasing 21,100 J of heat. What is the specific heat capacity of brass in $$\mathrm{J/g\cdot K}$$?

$$c = \frac{21,100}{590 \times 91.2} = 0.392 \ \mathrm{J/g\cdot K}$$

Q: A 225 g sample of water is heated from 25.0°C to 100.0°C. How much heat (in calories) is required? (Specific heat of water $$c = 1.00 \ \mathrm{cal/g\cdot ^\circ C})$$

$$q = 225 \times 1.00 \times (100.0 - 25.0) = 16,875 \ \mathrm{cal}$$

Question 1

Which molecular interaction is primarily responsible for water's high boiling point and its expansion upon freezing?

Accepted Answer

Hydrogen bonding

Question 2

Water is described as amphoteric. What does this mean?

Accepted Answer

It can act as both an acid and a base.

Question 3

Calculate the amount of heat (in joules) required to raise the temperature of 150 g of water from 20.0°C to 80.0°C. (Specific heat of water $$c = 4.18 \ \mathrm{J/g\cdot K})$$

Accepted Answer

$$q = 150 	imes 4.18 	imes (80.0 - 20.0) = 37,620 \ \mathrm{J}$$

Question 4

A brass candlestick (mass = 0.59 kg) cools from 98.0°C to 6.8°C, releasing 21,100 J of heat. What is the specific heat capacity of brass in $$\mathrm{J/g\cdot K}$$?

Accepted Answer

$$c = \frac{21,100}{590 	imes 91.2} = 0.392 \ \mathrm{J/g\cdot K}$$

Question 5

Which of the following best explains why water is considered a 'universal solvent'?

Accepted Answer

Water's polarity and hydrogen bonding allow it to dissolve many ionic and polar substances.

Question 6

A Pikachu gives a shock of 360 J. How many calories is this? ($$1 \ \mathrm{cal} = 4.184 \ \mathrm{J})$$

Accepted Answer

$$360 \div 4.184 = 86 \ \mathrm{cal}$$

Question 7

Which process in the water cycle is responsible for the conversion of liquid water to water vapor?

Accepted Answer

Evaporation

Question 8

Which of the following is a point source of water pollution?

Accepted Answer

Effluent from a factory pipe

Question 9

Which pollutant is most associated with 'blue baby syndrome' due to contamination of groundwater?

Accepted Answer

Nitrate

Question 10

Which process is most responsible for the removal of colloidal particles and bacteria in the first step of municipal water treatment?

Accepted Answer

Addition of slaked lime and alum to form aluminum hydroxide

Question 11

Which method is most commonly used for disinfection of municipal drinking water?

Accepted Answer

Chlorination

Question 12

What is the main environmental concern associated with the process of desalination?

Accepted Answer

It produces large amounts of brine waste.

Question 13

Which of the following best describes cultural eutrophication?

Accepted Answer

An increase in algae growth due to human-introduced nutrients.

Question 14

Which of the following is the largest consumer of water worldwide?

Accepted Answer

Irrigation

Question 15

A 225 g sample of water is heated from 25.0°C to 100.0°C. How much heat (in calories) is required? (Specific heat of water $$c = 1.00 \ \mathrm{cal/g\cdot ^\circ C})$$

Accepted Answer

$$q = 225 	imes 1.00 	imes (100.0 - 25.0) = 16,875 \ \mathrm{cal}$$

Question 16

Which of the following is a consequence of water stress in a region?

Accepted Answer

Subsidence (sinking of land)

Question 17

Which of the following substances, when added to drinking water, has been shown to reduce tooth decay?

Accepted Answer

Fluoride

Question 18

Which wastewater treatment process involves holding sewage in settling ponds to allow solids to precipitate out as sludge?

Accepted Answer

Primary treatment

Question 19

Which of the following is a major source of volatile organic chemicals (VOCs) contaminating groundwater?

Accepted Answer

Leaking underground storage tanks

Question 20

Which of the following water conservation strategies is most effective for reducing agricultural water consumption?

Accepted Answer

Installing drip irrigation systems

Chapter 14: Water – Properties, Distribution, and Environmental Chemistry

Guida di studio - Domande di pratica

Study guide - Flashcard