Question 1

Which of the following statements best explains why NF$$_3$$ has a smaller dipole moment than NH$$_3$$, even though the N–F bond is more polar than the N–H bond?

Accepted Answer

The lone pairs on nitrogen in NF$$_3$$ are oriented to partially cancel the bond dipoles, resulting in a smaller overall dipole moment.

Question 2

Which intermolecular force is primarily responsible for the high boiling point of water compared to methane?

Accepted Answer

Hydrogen bonding

Question 3

Rank the following compounds in order of increasing boiling point: neopentane, n-hexane, 2,3-dimethylbutane, pentan-1-ol, 2-methylbutan-2-ol.

Accepted Answer

neopentane \u003c 2,3-dimethylbutane \u003c n-hexane \u003c 2-methylbutan-2-ol \u003c pentan-1-ol

Question 4

Which of the following molecules can act as a hydrogen bond donor?

Accepted Answer

CH$$_3CH$_2CH$_2OH$$

Question 5

Which of the following best describes the effect of branching on the boiling point of alkanes?

Accepted Answer

Branching decreases the boiling point because the molecule becomes more spherical and has less surface area.

Question 6

Which of the following is the strongest acid based on the given pK$$_a$$ values: HCl (pK$$_a = -7$$), CH$$_3$$COOH (pK$$_a = 4.76$$), H$$_2O (pK$_a = 15.7$$), NH$$_3 (pK$_a = 36$$)?

Accepted Answer

HCl

Question 7

Which of the following solvents would be most compatible for an acid-base reaction involving CH$$_3Li $$and HCCH, considering the stability of the products?

Accepted Answer

Pentane

Question 8

Which of the following statements about London dispersion forces is correct?

Accepted Answer

They result from temporary dipoles induced in atoms or molecules.

Question 9

Which of the following pairs of compounds is more soluble in water?

Accepted Answer

CH$$_3CH$_2CH$_2OH or CH$_3CH$_2CH$_2CH$_2CH$_3$$

Question 10

Which of the following is a Brønsted–Lowry base?

Accepted Answer

NH$$_3$$

Question 11

What is the relationship between the strength of an acid and its conjugate base?

Accepted Answer

A stronger acid has a weaker conjugate base.

Question 12

Which of the following molecules will have the largest molecular dipole moment?

Accepted Answer

Formaldehyde (CH$$_2O)$$

Question 13

Which of the following functional groups is present in both aldehydes and ketones?

Accepted Answer

Carbonyl group (C=O)

Question 14

Which of the following statements about hydrogen bonding is true?

Accepted Answer

Hydrogen bonding occurs in molecules with N–H or O–H groups.

Question 15

Which of the following compounds is classified as an amide?

Accepted Answer

CH$$_3$$CONH$$_2$$

Question 16

Which of the following best describes a Lewis acid?

Accepted Answer

A species that accepts a pair of electrons

Question 17

Which of the following effects will increase the acidity of a molecule?

Accepted Answer

Increasing resonance stabilization of the conjugate base

Question 18

Which of the following statements about solubility is correct?

Accepted Answer

Polar solutes dissolve in polar solvents.

Question 19

Which of the following compounds contains a cyano group?

Accepted Answer

CH$$_3CH$_2CN$$

Question 20

Which of the following is the correct formula for calculating pK$$_a$$ from K$$_a$$?

Accepted Answer

$$pK_a = -\log K_a$$

Unit 2

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드