Q: Which equation correctly represents the calculation for the amount of heat required to raise the temperature of a substance?

$$\text{Heat} = \text{mass} \times \Delta T \times \text{specific heat}$$

Q: Which formula is used to calculate the heat required for a phase change from solid to liquid?

$$\text{Heat} = \text{mass} \times \text{heat of fusion}$$

Question 1

Which of the following is an example of a homogeneous mixture?

Accepted Answer

Air composed of nitrogen, oxygen, and other gases

Question 2

Which statement best describes a chemical property?

Accepted Answer

Iron reacts with oxygen to form rust

Question 3

A student mixes oil and water in a beaker. After shaking, the oil floats on top of the water. This mixture is best classified as:

Accepted Answer

A heterogeneous mixture

Question 4

Which of the following is a physical change?

Accepted Answer

Dissolving sugar in water

Question 5

Which equation correctly represents the calculation for the amount of heat required to raise the temperature of a substance?

Accepted Answer

$$	ext{Heat} = 	ext{mass} 	imes \Delta T 	imes 	ext{specific heat}$$

Question 6

Which process describes a change from solid directly to gas without passing through the liquid phase?

Accepted Answer

Sublimation

Question 7

A sample of ethanol ($$	ext{CH}_3	ext{CH}_2	ext{OH}) $$requires $$26.3$$ cal to melt $$1 g at $$its freezing point. What is this amount of heat called?

Accepted Answer

Heat of fusion

Question 8

Which of the following is NOT a physical property?

Accepted Answer

Ability to react with acid

Question 9

A student heats $$100 g of $$water from $$25^\	ext{o}C to$$ $$75^\	ext{o}C. If $$the specific heat of water is $$1.0$$ cal/g$$^\	ext{o}C$$, how much heat is required?

Accepted Answer

$$5000$$ cal

Question 10

Which of the following best describes a compound?

Accepted Answer

A substance made up of two or more elements chemically combined in a fixed ratio

Question 11

Which of the following is an example of a chemical change?

Accepted Answer

Burning gasoline in a car engine

Question 12

What is the heat of vaporization?

Accepted Answer

The energy required to convert 1 g of liquid to gas at its boiling point

Question 13

Which formula is used to calculate the heat required for a phase change from solid to liquid?

Accepted Answer

$$	ext{Heat} = 	ext{mass} 	imes 	ext{heat of fusion}$$

Question 14

A nurse needs to sterilize surgical instruments by boiling them in water. Which physical property is most relevant to this process?

Accepted Answer

Boiling point

Question 15

Which of the following statements about mixtures is TRUE?

Accepted Answer

Mixtures have variable composition

Question 16

A patient receives an ice pack for a sprained ankle. The cooling effect is due to which process?

Accepted Answer

Fusion (melting)

Question 17

Which of the following is a correct statement about energy?

Accepted Answer

Kinetic energy is the energy of motion

Question 18

A student wants to separate a mixture of sand and salt. Which method would be most effective?

Accepted Answer

Filtration followed by evaporation

Question 19

Which of the following is NOT a chemical property?

Accepted Answer

Melting point

Question 20

A sample of $$50 g of $$ethanol ($$	ext{CH}_3	ext{CH}_2	ext{OH}) is $$vaporized at its boiling point. If the heat of vaporization is $$202$$ cal/g, how much heat is required?

Accepted Answer

$$10,100$$ cal

Fundamentals of Matter, Properties, and Energy in GOB Chemistry

Guida di studio - Domande di pratica

Study guide - Flashcard