Quiz - Alkanes - 2 | Alkanes

Organic Chemistry 1 - Quiz - Alkanes - 2

1

What is the correct IUPAC name for the linear alkane with the chemical formula C7H16?

The correct IUPAC name for C7H16 is Heptane. It has a straight chain of seven carbon atoms with no branching, hence no need for numbers in its naming. 'Hept-' indicates seven carbon atoms, and '-ane' indicates single bonds between the carbon atoms.

2

In an alkane, what do the terms primary, secondary, tertiary, and quaternary specifically refer to?

The terms primary, secondary, tertiary, and quaternary refer to the number of other carbon atoms attached to a given carbon atom. A primary carbon is attached to one other carbon, a secondary to two, a tertiary to three, and a quaternary carbon to four other carbon atoms. This classification is important for understanding reactivity and substitution patterns.

3

Which alkane property is primarily determined by the dispersion forces among its molecules?

The boiling point of an alkane is primarily determined by the strength of the dispersion forces among its molecules. As the size of the alkane increases, the surface area and the strength of the dispersion forces increase, leading to a higher boiling point. The other properties listed are not primarily affected by dispersion forces.

4

What is the primary reason that radical halogenation of alkanes is considered a chain reaction?

Radical halogenation of alkanes is a chain reaction because it involves multiple steps that propagate the reaction. The key steps include initiation (generation of radicals), propagation (radicals generate more radicals), and termination (radicals combine to form stable products). This process can continue and generate many products from a single initiation event.

5

What is the IUPAC name of the alkane with the following structure: CH3-CH2-CH(CH3)-CH(CH3)2?

The longest continuous chain in this molecule has five carbon atoms, which makes it a pentane. The side group (methyl group) is attached to the second and the third carbons of the chain, giving it the IUPAC name 2,3-dimethylpentane.

6

Which type of radical is most likely to be formed during the halogenation of 2-methylbutane?

During halogenation of alkanes, the tertiary hydrogen is the most likely to be abstracted because tertiary radicals are the most stable due to hyperconjugation and the inductive effect. 2-methylbutane has tertiary hydrogen atoms, which will preferentially form tertiary radicals.

7

The process of separating a complex mixture of alkanes into simpler fractions based on boiling point is known as:

Fractional distillation is the process used to separate a complex mixture of alkanes into simpler fractions based on their boiling points. This is due to differences in the strengths of their van der Waals' forces, which correlate with molecular size and shape.

8

Which term describes the hydrocarbon radicals that can form when alkanes are broken down under certain conditions?

Alkyl radicals are the correct term for the hydrocarbon radicals that can form when alkanes break down under conditions such as those in radical halogenation. These radicals play a crucial role in the chain reaction mechanism.

9

What defines chemically equivalent atoms?

Chemically equivalent atoms are those with an identical environment, which is crucial in spectroscopy and reactions.

10

Which statement accurately describes the reactivity of alkanes?

Alkanes are known for their low reactivity due to the strong σ bonds between carbon atoms, making them generally unreactive under normal conditions.