【GR1727】 The Solution for GRE Chemistry Practice Test [01-20]

The Solution for GRE Chemistry Practice Test [01-20]

 

추천글 : 【GRE】 Solution for GRE Chemistry Practice Test 

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1. Which of the following is the major product of the reaction shown below?

 

 

⑴ answer: D

⑵ Grignard reagent carbon-carbon coupling reaction 

 

 

2. According to IUPAC rules, what is the name of the molecule shown below?

 

⑴ answer: E

⑵ ester nomenclature 

 

 

3. Of the following, which has the smallest radius?

 

 

⑴ answer: C

⑵ The radius decreases as the atomic number increases when the number of electrons is constant.

⑶ In general, the radius increases as the number of shells increases.

 

 

4. The molecular geometry of thionyl chloride, SOCl₂, is best described as 

 

 

⑴ answer: D

⑵ The molecular geometry is based on VSEPR.

 

 

 

5. Which of the following is true of the cell represented below?

 

 

⑴ answer: A

⑵ The problem is based on electrochemistry.

⑶ oxidation: losing one or more electrons

⑷ reduction: getting one or more electrons

⑸ An oxidizing agent itself reduces.

⑹ A reducing agent itself oxidizes.

⑺ If ions are generated, they do neither oxidize nor reduce.

 

 

6. Of the following substances, which is likely to have the largest value of the coefficient a in the van der Waals equation of state for real gases shown below? 

 

 

⑴ answer: D

⑵ Van der Waals equation of state 

⑶ If the intermolecular attraction is more strong due to polarity, etc, the coefficient a is larger.

 

 

7. What is the orbital angular momentum quantum number, ℓ, of the electron that is most easily removed when ground-state aluminum is ionized? 

 

 

⑴ answer: C

⑵ basics of quantum number 

⑶ Al: 1s²2s²2p⁶3s²3p¹  

 

 

8. When the equation shown below is balanced, which of the follownig is true? 

 

 

⑴ answer: B

⑵ determination of the reaction coefficients

⑶ 6MnO₄^- + 5I^- + 18H⁺ → 6Mn²⁺ + 5IO₃^- + 9H₂O 

 

 

9. Which of the following is the major organic product of the reaction shown below?

 

 

⑴ answer: C

⑵ carboxylic acid reduction reaction 

⑶ The reaction goes to aldehyde at first, and to primary alcohol afterward.

 

 

10. All of the following are aromatic EXCEPT 

 

 

⑴ answer: D

⑵ Hückel's rule 

 

 

11. In a DNA double-helix, guanine and cytosine bases, shown below, are paired together by 

 

 

⑴ answer: B 

 

 

12. Of the following isomers, which is the most thermodynamically stable? 

 

 

⑴ answer: B 

⑵ If its substituent is equatorial, the molecule is stable.

 

 

13. Under constant current electrolysis, how many coulombs would be required to reduce 2 mol of Cu²⁺ to metallic copper? (ℱ = 96,500 coulombs/mol)

 

 

⑴ answer: E 

⑵ 96,500 coulombs/mol × 2 mol Cu²⁺ × 2 mol e^- / mol Cu²⁺ = 386,000 coulombs 

 

 

14. For the reaction A + B → C + D carried out at constant temperature, the initial rates of reaction given below were found experimentally. The rate law of this reaction, expressed as a function of reactant concentrations, is 

 

 

⑴ answer: D

⑵ When comparing the first and the second rows of the table, we could know the order of [A] is 1.

⑶ When comparing the second and the third rows of the table, we could know the order of [B] is 2.

 

 

15. Which of the following must be true about a binary liquid mixture that obeys Raoult's law?

Ⅰ. The partial pressure of each component at equilibrium is proportional to its mole fraction in the liquid mixture.

Ⅱ. The volume of the mixture is equal to the sum of the volumes of each component before mixing. 

Ⅲ. Intermolecular interactions in the mixture are identical to intermolecular interactions in the pure components. 

 

 

⑴ answer: E 

 

 

16. In the reaction shown below, Cl^- (aq) behaves as 

 

 

⑴ answer: E

⑵ oxidation number of Cl^- (reduced) : -1

⑶ oxidation number of HClO₂ (oxidized) : +3

 

 

17. Elements with partially filled 4f or 5f orbitals include all of the following EXCEPT  

 

 

⑴ answer: A

⑵ Cu: [Ar] 3d¹⁰ 4s¹

⑶ Gd: [Xe] 4f⁷ 5d¹ 6s²

⑷ Eu: [Xe] 4f⁷ 6s²

⑸ Am: [Rn] 5f⁷ 7s²

⑹ Cm: [Rn] 5f⁷ 6d¹ 7s² 

 

 

18. Which of the following gives the multiplicities of the signals for the protons designated H_A and H_B in the ¹H NMR spectrum of the compound shown below? 

 

 

⑴ answer: E

⑵ The number of the neighboring hydrogens to H_A is 3. → quartet 

⑶ The number of the neighboring hydrogens to H_B is 0. → singlet 

 

 

19. In the compound shown below, which hydrogen is most easily abstracted in a free radical bromination reaction?

 

 

⑴ answer: D

⑵ The stability comparison of radicals is as follow: phenyl radical ＜ vinyl radical ＜ methyl radical ＜ primary radical ＜ secondary radical ＜ tertiary radical ≪ allyl radical ＜ benzyl radical.

 

 

20. Which of the following is the major product of the reaction shown below? 

 

 

⑴ answer: C

⑵ acid-base reaction of alkyne 

 

입력: 2022.03.01 12:07