Q: 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 which formula should be used?

Density = $$\frac{\text{mass}}{\text{volume}}$$; Density = $$\frac{12.34}{4.56} = 2.71 g/mL$$

Q: Which of the following is the correct balanced equation for the reaction of hydrogen gas with oxygen gas to form water?

$$2\text{H}_2 + \text{O}_2 \rightarrow 2\text{H}_2\text{O}$$

Q: Which of the following is the correct formula for calculating percent error in a laboratory experiment?

$$\text{Percent Error} = \frac{\text{Experimental Value} - \text{Accepted Value}}{\text{Accepted Value}} \times 100\%$$

Question 1

Which of the following best describes the difference between a physical change and a chemical change?

Accepted Answer

A physical change does not alter the chemical composition of a substance, while a chemical change results in the formation of new substances.

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 which formula should be used?

Accepted Answer

Density = $$\frac{	ext{mass}}{	ext{volume}}$$; Density = $$\frac{12.34}{4.56} = 2.71 g/mL$$

Question 3

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

Accepted Answer

Sand and iron filings

Question 4

Which piece of laboratory equipment would you use to accurately measure the volume of a liquid?

Accepted Answer

Graduated cylinder

Question 5

A student needs to convert 25.0 °C to Kelvin. Which formula should be used, and what is the correct answer?

Accepted Answer

$$K = °C + 273.15$$; K = 25.0 + 273.15 = 298.15\ K$

Question 6

Which of the following statements about atomic structure is correct?

Accepted Answer

Protons have a positive charge and are found in the nucleus.

Question 7

Which of the following is the correct balanced equation for the reaction of hydrogen gas with oxygen gas to form water?

Accepted Answer

$$2	ext{H}_2 + 	ext{O}_2 ightarrow 2	ext{H}_2	ext{O}$$

Question 8

A compound contains 40.0% carbon, 6.7% hydrogen, and 53.3% oxygen by mass. What is the empirical formula of the compound?

Accepted Answer

$$	ext{CH}_2	ext{O}$$

Question 9

Which of the following best describes the role of a catalyst in a chemical reaction?

Accepted Answer

A catalyst speeds up the reaction without being consumed.

Question 10

A student mixes two clear solutions and observes the formation of a solid. What type of chemical reaction has occurred?

Accepted Answer

Precipitation

Question 11

Which of the following is a correct safety procedure when working in a chemistry laboratory?

Accepted Answer

Always wear safety goggles when handling chemicals.

Question 12

Which of the following is the correct formula for calculating percent error in a laboratory experiment?

Accepted Answer

$$	ext{Percent Error} = \frac{	ext{Experimental Value} - 	ext{Accepted Value}}{	ext{Accepted Value}} 	imes 100\%$$

Question 13

Which of the following best explains why water is considered a polar molecule?

Accepted Answer

Water has a bent shape and unequal sharing of electrons.

Question 14

A student is asked to prepare 250 mL of a 0.50 M NaCl solution. How many moles of NaCl are required?

Accepted Answer

$$0.125$$ moles

Question 15

Which of the following is NOT a property of metals?

Accepted Answer

Brittle

Question 16

Which of the following best describes the difference between an ionic bond and a covalent bond?

Accepted Answer

Ionic bonds involve the transfer of electrons, while covalent bonds involve the sharing of electrons.

Question 17

A student records the following data for a reaction: Initial temperature = 22.0°C, Final temperature = 28.0°C. What is the change in temperature ($$\Delta T$$)?

Accepted Answer

$$\Delta T = 6.0^\circ	ext{C}$$

Question 18

Which of the following is a correct example of a chemical property?

Accepted Answer

Reactivity with acid

Question 19

Which of the following is the correct formula for calculating molarity ($$M$$)?

Accepted Answer

$$M = \frac{	ext{moles of solute}}{	ext{liters of solution}}$$

Principles of Chemistry (CHEM 101) Syllabus and Study Guide

Study Guide - Practice Questions

Study Guide - Flashcards