$$120\ \mathrm{cm} \times \frac{1\ \mathrm{m}}{100\ \mathrm{cm}} = 1.2\ \mathrm{m}$$

Question 1

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

Accepted Answer

A chemical property is related to the ability of a substance to undergo a specific chemical change.

Question 2

A sample of metal has a mass of 45.0 g and a volume of 15.0 mL. What is its density?

Accepted Answer

$$\frac{45.0\ \mathrm{g}}{15.0\ \mathrm{mL}} = 3.0\ \mathrm{g/mL}$$

Question 3

Which of the following is the correct symbol for the element potassium?

Accepted Answer

K

Question 4

A chemical reaction absorbs heat from its surroundings. Which term best describes this process?

Accepted Answer

Endothermic

Question 5

Convert 0.00056 to scientific notation.

Accepted Answer

$$5.6 	imes 10$$^{-4}$$

Question 6

How many significant figures are in the measurement 0.00450?

Accepted Answer

3

Question 7

Which of the following is NOT a step in the scientific method?

Accepted Answer

Ignoring contradictory evidence

Question 8

A student measures the temperature of a solution as 25°C. What is this temperature in Kelvin?

Accepted Answer

$$25 + 273.15 = 298.15\ \mathrm{K}$$

Question 9

Which of the following best describes a mixture?

Accepted Answer

A combination of two or more substances in which each retains its own identity

Question 10

Which of the following ions has a charge of $$+2$$?

Accepted Answer

$$\mathrm{Mg}^{2+}$$

Question 11

What is the chemical formula for a binary ionic compound formed between magnesium and chlorine?

Accepted Answer

$$\mathrm{MgCl}_2$$

Question 12

Which of the following is a diatomic element?

Accepted Answer

Oxygen

Question 13

A student needs to convert 120 cm to meters using dimensional analysis. What is the correct conversion?

Accepted Answer

$$120\ \mathrm{cm} 	imes \frac{1\ \mathrm{m}}{100\ \mathrm{cm}} = 1.2\ \mathrm{m}$$

Question 14

Which of the following best describes an exothermic reaction?

Accepted Answer

A reaction that releases heat to the surroundings

Question 15

Which of the following is the correct electron configuration for a neutral sodium atom?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^6$$\ $$3s^1$$

Question 16

Which of the following is a correct statement about the periodic table?

Accepted Answer

Elements in the same group have similar chemical properties.

Question 17

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

$$\mathrm{CH}_2\mathrm{O}$$

Question 18

Which of the following is the correct way to determine the number of significant figures in the result of $$2.50 	imes 3.0$$?

Accepted Answer

The result should have the same number of significant figures as the number with the fewest significant figures.

Question 19

Which of the following is the correct charge for the sulfate ion?

Accepted Answer

$$\mathrm{SO}_4$$^{2-}$$

Question 20

A patient receives 500 mg of a medication. How many grams is this?

Accepted Answer

$$500\ \mathrm{mg} 	imes \frac{1\ \mathrm{g}}{1000\ \mathrm{mg}} = 0.5\ \mathrm{g}$$

Exam 1 Study Guide: Introduction to Chemistry Core Concepts

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