Question 1

Which of the following best describes the difference between a scientific law and a scientific theory?

Accepted Answer

A scientific law is a summary of observed behavior, while a theory provides an explanation for that behavior.

Question 2

A student measures the mass of a sample as 12.34 g and its volume as 4.56 mL. What is the density of the sample, and how many significant figures should the answer have?

Accepted Answer

2.706 g/mL, 4 significant figures

Question 3

Which of the following is an example of an endothermic process?

Accepted Answer

Melting of ice in a glass of water

Question 4

A sample of gold has a mass of 96.5 g and a density of 19.3 g/cm$$^3. $$What is its volume?

Accepted Answer

$$5.00\ \mathrm{cm}^3$$

Question 5

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

Accepted Answer

The total mass of reactants equals the total mass of products in a chemical reaction.

Question 6

Convert $$3.50\ \mathrm{km} to $$centimeters using dimensional analysis.

Accepted Answer

$$350,000\ \mathrm{cm}$$

Question 7

Which of the following is a chemical property?

Accepted Answer

Flammability

Question 8

A student records the following measurements: 2.50 m, 0.0450 m, and 0.00300 m. How many significant figures are in each measurement, respectively?

Accepted Answer

3, 3, 3

Question 9

Which of the following best describes a homogeneous mixture?

Accepted Answer

A mixture in which the composition is uniform throughout

Question 10

A reaction absorbs 150 J of heat and involves 0.50 mol of substance. What is the sign of $$q$$ and is the reaction endothermic or exothermic?

Accepted Answer

$$q is $$positive; the reaction is endothermic.

Question 11

Which of the following is the correct SI unit for measuring energy?

Accepted Answer

Joule

Question 12

A 250.0 g sample of water is heated from $$22.0\ ^\circ\mathrm{C} to$$ $$98.0\ ^\circ\mathrm{C}. If $$the specific heat capacity of water is $$4.18\ \mathrm{J}/(\mathrm{g}\cdot ^\circ\mathrm{C})$$, how much heat ($$q) is $$absorbed?

Accepted Answer

$$79,100\ \mathrm{J}$$

Question 13

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

Accepted Answer

Boiling of water

Question 14

Convert $$25.0\ ^\circ\mathrm{C} to $$Kelvin.

Accepted Answer

$$298.15\ \mathrm{K}$$

Question 15

Which of the following best describes potential energy?

Accepted Answer

Energy stored due to position or composition

Question 16

A solution is prepared by dissolving 10.0 g of NaCl in 100.0 g of water. Which of the following best describes the resulting mixture?

Accepted Answer

Homogeneous mixture

Question 17

Which of the following is the correct scientific notation for the number 0.000560?

Accepted Answer

$$5.60 	imes 10$$^{-4}$$

Question 18

A rectangular block has dimensions $$2.00\ \mathrm{cm} 	imes 3.00\ \mathrm{cm} 	imes 4.00\ \mathrm{cm}$$ and a mass of $$96.0\ \mathrm{g}. $$What is its density?

Accepted Answer

$$1.00\ \mathrm{g/cm}^3$$

Question 19

Which of the following is NOT an SI base unit?

Accepted Answer

Gram

Question 20

A car engine releases 500 kJ of energy as heat during combustion. If $$1\ \mathrm{cal} = 4.184\ \mathrm{J}$$, how many kilocalories is this?

Accepted Answer

$$119.5\ \mathrm{kcal}$$

Introductory Chemistry: Foundations of Matter, Measurement, and Energy

Guida di studio - Domande di pratica

Study guide - Flashcard