Question 1

A student measures the mass of a metal sample as 12.34 g and its volume as 4.56 mL. What is the density of the metal, reported with the correct number of significant figures?

Accepted Answer

$$2.7\ \mathrm{g/mL}$$

Question 2

Which of the following statements best describes Dalton’s atomic theory as it relates to modern chemistry?

Accepted Answer

Atoms combine in simple whole-number ratios to form compounds.

Question 3

A solution is prepared by dissolving 5.00 g of NaCl in enough water to make 250.0 mL of solution. What is the molarity of the solution? ($$\mathrm{NaCl}$$ molar mass = $$58.44\ \mathrm{g/mol})$$

Accepted Answer

$$0.342\ \mathrm{M}$$

Question 4

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

Accepted Answer

Melting of ice

Question 5

A chemical reaction is carried out in a closed container. The total mass of the reactants is 50.0 g. After the reaction, the total mass of the products is found to be 49.8 g. Which law is being tested, and what is the most likely explanation for the result?

Accepted Answer

Law of Conservation of Mass; a small amount of product was lost during the experiment.

Question 6

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

Accepted Answer

Ionic bonds involve the transfer of electrons from one atom to another, while covalent bonds involve the sharing of electrons between atoms.

Question 7

A sample of gas occupies $$2.50\ \mathrm{L} at$$ $$1.00\ \mathrm{atm}$$ and $$25^\circ\mathrm{C}. $$What will be its volume at $$0.500\ \mathrm{atm}$$ and $$25^\circ\mathrm{C}$$, assuming ideal gas behavior?

Accepted Answer

$$5.00\ \mathrm{L}$$

Question 8

Which of the following best explains why water has a higher boiling point than methane ($$\mathrm{CH_4$}$$)?

Accepted Answer

Water forms hydrogen bonds, which are stronger than the London dispersion forces in methane.

Question 9

Which of the following is the correct electron configuration for a neutral atom of sulfur ($$Z=16$$)?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^6$$\ $$3s^2$$\ $$3p^4$$

Question 10

Which of the following statements about the kinetic-molecular theory of gases is correct?

Accepted Answer

Gas particles are in constant, random motion and their collisions are perfectly elastic.

Question 11

A 10.0 g sample of calcium carbonate ($$\mathrm{$$CaCO_3$$}) is $$heated and decomposes according to the equation: $$\mathrm{$$CaCO_3$$(s) \rightarrow CaO(s) + CO_2$(g)}. $$What is the theoretical yield of $$\mathrm{CO_2$} in $$grams? (Molar masses: $$\mathrm{$$CaCO_3$$} = 100.1\ \mathrm{g/mol}$$, $$\mathrm{CO_2$} = 44.0\ \mathrm{g/mol})$$

Accepted Answer

$$4.39\ \mathrm{g}$$

Question 12

Which of the following best describes the concept of electronegativity?

Accepted Answer

The ability of an atom to attract electrons in a chemical bond.

Question 13

Which of the following molecules is nonpolar, despite having polar bonds?

Accepted Answer

$$\mathrm{CO_2$}$$

Question 14

A reaction has $$\Delta H = -125\ \mathrm{kJ}$$ and $$\Delta S = +50\ \mathrm{J/K}. At $$what temperature (in K) does the reaction become nonspontaneous? ($$\Delta G = \Delta H - T\Delta S)$$

Accepted Answer

$$2500\ \mathrm{K}$$

Question 15

Which of the following best explains why salt ($$\mathrm{NaCl}) $$dissolves in water?

Accepted Answer

Water molecules form hydrogen bonds with sodium and chloride ions, stabilizing them in solution.

Question 16

Which of the following is the correct Lewis structure for ammonia ($$\mathrm{NH_3$}$$)?

Accepted Answer

Nitrogen atom with three single bonds to hydrogen atoms and one lone pair on nitrogen.

Question 17

Which of the following best describes the VSEPR theory prediction for the shape of $$\mathrm{CH_4$} ($$methane)?

Accepted Answer

Tetrahedral

Question 18

A sample of oxygen gas at $$25^\circ\mathrm{C}$$ and $$1.00\ \mathrm{atm}$$ has a volume of $$10.0\ \mathrm{L}. $$How many moles of oxygen gas are present? ($$R = 0.0821\ \mathrm{L\cdot atm\cdot $$mol^{-1}$$\cdot K$$^{-1}$$})$$

Accepted Answer

$$0.409\ \mathrm{mol}$$

Question 19

Which of the following is a redox reaction?

Accepted Answer

$$\mathrm{2H_2 + O_2$ \rightarrow 2H_2O}$$

Question 20

Which of the following statements about intermolecular forces is correct?

Accepted Answer

London dispersion forces are present in all molecules, regardless of polarity.

General Chemistry I (CHEM 1307) Syllabus and Study Guide

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드