Question 1

Which of the following correctly represents the balanced nuclear equation for the beta decay of carbon-14?

Accepted Answer

$$^{14}_{6}\mathrm{C} \$$rightarrow ^{14}$$_{7}\mathrm{N} $$+ ^{0}$$_{-1}\mathrm{e}$$

Question 2

A hospital uses technetium-99m ($$^{99m}_{43}\mathrm{Tc}) $$for imaging. If the half-life of $$^{99m}_{43}\mathrm{Tc} is 6 $$hours, how much of a 32 mg sample remains after 18 hours?

Accepted Answer

4 mg

Question 3

Which of the following statements about nuclear fission and fusion is correct?

Accepted Answer

Fusion combines light nuclei to form a heavier nucleus, releasing more energy per nucleon than fission.

Question 4

Which of the following is the correct formula for the ionic compound formed between iron(III) and sulfate?

Accepted Answer

$$\mathrm{Fe}_2(\mathrm{SO}_4)_3$$

Question 5

Which of the following best describes the bonding and structure in carbon dioxide ($$\mathrm{CO}_2$$)?

Accepted Answer

Linear molecule with two polar bonds but overall nonpolar

Question 6

Which of the following pairs of elements will form an ionic compound?

Accepted Answer

Sodium and chlorine

Question 7

What is the correct Lewis structure for ammonia ($$\mathrm{NH}_3$$)?

Accepted Answer

Nitrogen with three single bonds to hydrogen and one lone pair

Question 8

Which of the following best explains why ionic compounds have high melting points?

Accepted Answer

Strong electrostatic forces between oppositely charged ions require a lot of energy to break

Question 9

Which of the following is the correct balanced chemical equation for the combustion of methane ($$\mathrm{CH}_4$$)?

Accepted Answer

$$\mathrm{CH}_4 + 2\mathrm{O}_2 \rightarrow \mathrm{CO}_2 + 2\mathrm{H}_2\mathrm{O}$$

Question 10

How many molecules are present in 0.25 moles of water ($$\mathrm{H}_2\mathrm{O}$$)?

Accepted Answer

$$1.51 	imes 10$$^{23}$$

Question 11

A reaction has a theoretical yield of 10.0 g, but only 7.5 g of product is obtained. What is the percent yield?

Accepted Answer

$$75\%$$

Question 12

Which of the following best describes an exothermic reaction?

Accepted Answer

A reaction that releases heat to the surroundings

Question 13

Which of the following is the limiting reactant when 5.0 g of hydrogen reacts with 20.0 g of oxygen to form water ($$\mathrm{H}_2\mathrm{O}$$)?

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

Accepted Answer

Hydrogen

Question 14

A sample of gas has a volume of 2.0 L at 1.0 atm. If the pressure is increased to 4.0 atm at constant temperature, what is the new volume?

Accepted Answer

0.5 L

Question 15

Which of the following is NOT a property of gases?

Accepted Answer

Definite shape

Question 16

Which of the following best explains the role of carbon dioxide in blood gas transport?

Accepted Answer

It is transported as bicarbonate ion ($$\mathrm{HCO}_3^-) in $$plasma

Question 17

Which of the following is the correct name for $$\mathrm{N}_2\mathrm{O}_4$$?

Accepted Answer

Dinitrogen tetroxide

Question 18

Which of the following statements about electronegativity and bond polarity is correct?

Accepted Answer

A bond between atoms with a large difference in electronegativity is polar

Question 19

Which of the following is the correct formula for the polyatomic ion phosphate?

Accepted Answer

$$\mathrm{PO}_4$$^{3-}$$

Question 20

A 5.0 g sample of sodium chloride ($$\mathrm{NaCl}) is $$dissolved in water. What is the number of moles of $$\mathrm{NaCl}$$? ($$\mathrm{NaCl}$$ molar mass = 58.44 g/mol)

Accepted Answer

0.086 mol

Exam 2 Study Guide: Nuclear Chemistry, Ionic & Molecular Compounds, Chemical Reactions, and Gases

Guida di studio - Domande di pratica

Study guide - Flashcard