Question 1

Which of the following is the correct general molecular formula for alkynes?

Accepted Answer

$$C_nH_{2n-2}$$

Question 2

What is the correct IUPAC name for the compound with the structure $$CH_3C \equiv CCH_2CH_3$$?

Accepted Answer

2-pentino

Question 3

Which hybridization and geometry are characteristic of the carbon atoms in acetylene ($$C_2H_2$$)?

Accepted Answer

sp hybridization and linear geometry

Question 4

Which of the following best describes the bonding in the carbon-carbon triple bond of alkynes?

Accepted Answer

One $$\sigma$$ bond and two $$\pi$$ bonds

Question 5

When naming a molecule that contains both a double and a triple bond, which rule should be followed according to IUPAC nomenclature?

Accepted Answer

The chain is numbered from the end nearest the first multiple bond, and double bonds receive lower numbers than triple bonds if there is a choice.

Question 6

Which of the following statements about the physical properties of alkynes is correct?

Accepted Answer

Alkynes are slightly more polar and have slightly higher boiling points than the corresponding alkanes and alkenes.

Question 7

Which of the following is the correct IUPAC name for a compound with two triple bonds at positions 1 and 6 in a seven-carbon chain?

Accepted Answer

Hepta-1,6-diino

Question 8

What is the bond angle around each carbon atom in acetylene ($$C_2H_2$$)?

Accepted Answer

$$180^\circ$$

Question 9

Which of the following best explains why there are relatively few known cycloalkynes?

Accepted Answer

The linear geometry of the triple bond makes it difficult to form small rings.

Question 10

Given the following compounds, which one is an example of a terminal alkyne?

Accepted Answer

$$CH \equiv CCH_2CH_3$$

Question 11

Which of the following statements about the hybridization of carbon atoms in alkynes is correct?

Accepted Answer

Each carbon in the triple bond is sp hybridized, with two unhybridized 2p orbitals forming $$\pi$$ bonds.

Question 12

Which of the following is the correct IUPAC name for the compound with the structure $$CH_3C(CH_3$)_2C \equiv $$CCH_3$$?

Accepted Answer

4,4-dimetil-2-pentino

Question 13

Which of the following best describes the difference in bond length between the C–C bonds in ethane, ethene, and ethyne?

Accepted Answer

C–C bond length decreases from ethane to ethyne

Question 14

Which of the following is the correct order of percentage s-character in the hybrid orbitals of ethane, ethene, and ethyne?

Accepted Answer

Ethyne \u003e Ethene \u003e Ethane

Question 15

A compound is named 1-hepten-6-ino. Which functional groups are present and at which positions?

Accepted Answer

A double bond at C-1 and a triple bond at C-6

Question 16

Which of the following is a correct statement about the solubility of alkynes in water?

Accepted Answer

Alkynes are generally insoluble in water due to their nonpolar nature.

Question 17

Which of the following best explains why the boiling points of alkynes are slightly higher than those of corresponding alkanes and alkenes?

Accepted Answer

Alkynes are slightly more polar than alkanes and alkenes.

Question 18

Which of the following is the correct structural formula for 2-butyne?

Accepted Answer

$$CH_3C \equiv $$CCH_3$$

Question 19

Which of the following statements about the nomenclature of alkynes is correct?

Accepted Answer

The parent chain is numbered from the end nearest the triple bond.

Alquinos: Estructura, Nomenclatura y Propiedades

Study Guide - Practice Questions