Q: Which equation correctly relates heat energy, mass, specific heat capacity, and temperature change?

$$q = m \times C \times \Delta T$$

Q: A candy bar contains 225 Cal of nutritional energy. How many joules does it contain? (Given: $$1 \text{ Cal} = 1000 \text{ cal}$$, $$1 \text{ cal} = 4.184 \text{ J})$$

$$225 \times 1000 \times 4.184 = 941,400 \text{ J}$$

Q: Convert 25°C to Fahrenheit using the formula $$F = \frac{9}{5}C + 32.$$

$$F = \frac{9}{5} \times 25 + 32 = 77 \degree F$$

Q: A 2.5 g sample of gallium absorbs enough heat to raise its temperature from 25.0°C to 29.9°C. If the specific heat capacity of gallium is $$0.372 \text{ J/g} \degree C$$, what is the amount of heat absorbed? Use $$q = m \times C \times \Delta T.$$

$$q = 2.5 \times 0.372 \times (29.9 - 25.0) = 4.6 \text{ J}$$

Question 1

Which of the following best describes a crystalline solid?

Accepted Answer

Atoms or molecules are arranged in geometric patterns with long-range, repeating order.

Question 2

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

Accepted Answer

Boiling water to produce steam.

Question 3

A sample of matter is composed of only one type of atom. Which classification best fits this sample?

Accepted Answer

Element

Question 4

Which property is a chemical property?

Accepted Answer

The flammability of gasoline

Question 5

Which of the following statements about gases is correct?

Accepted Answer

Gases are compressible because their atoms or molecules are not in contact with one another.

Question 6

Which equation correctly relates heat energy, mass, specific heat capacity, and temperature change?

Accepted Answer

$$q = m 	imes C 	imes \Delta T$$

Question 7

A candy bar contains 225 Cal of nutritional energy. How many joules does it contain? (Given: $$1 	ext{ Cal} = 1000 	ext{ cal}$$, $$1 	ext{ cal} = 4.184 	ext{ J})$$

Accepted Answer

$$225 	imes 1000 	imes 4.184 = 941,400 	ext{ J}$$

Question 8

Which of the following is a heterogeneous mixture?

Accepted Answer

Hydrocarbon and water

Question 9

Which law states that matter is neither created nor destroyed in a chemical reaction?

Accepted Answer

Law of Conservation of Mass

Question 10

Which of the following is an endothermic process?

Accepted Answer

Melting of ice

Question 11

Convert 25°C to Fahrenheit using the formula $$F = \frac{9}{5}C + 32.$$

Accepted Answer

$$F = \frac{9}{5} 	imes 25 + 32 = 77 \degree F$$

Question 12

Which of the following best describes a compound?

Accepted Answer

A substance composed of two or more elements in fixed, definite proportions.

Question 13

Which of the following is NOT a unit of energy?

Accepted Answer

Kelvin (K)

Question 14

Which statement about temperature and heat is correct?

Accepted Answer

Temperature is a measure of the thermal energy of matter, while heat is the transfer of thermal energy.

Question 15

A 2.5 g sample of gallium absorbs enough heat to raise its temperature from 25.0°C to 29.9°C. If the specific heat capacity of gallium is $$0.372 	ext{ J/g} \degree C$$, what is the amount of heat absorbed? Use $$q = m 	imes C 	imes \Delta T.$$

Accepted Answer

$$q = 2.5 	imes 0.372 	imes (29.9 - 25.0) = 4.6 	ext{ J}$$

Question 16

Which of the following is a chemical change?

Accepted Answer

Burning butane in a lighter

Question 17

Which of the following best describes a homogeneous mixture?

Accepted Answer

A mixture with the same composition throughout

Question 18

Which form of energy is associated with the random motions of atoms and molecules in matter?

Accepted Answer

Thermal energy

Question 19

Which of the following statements about the law of conservation of energy is correct?

Accepted Answer

Energy is neither created nor destroyed; it can only be transferred or transformed.

Question 20

Which of the following is an example of a physical property?

Accepted Answer

The boiling point of water

Chapter 3: Matter and Energy – Structured Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard