Gasoline Is Primarily a Mixture of Hydrocarbons and Is Sold

question 13

Multiple Choice

Gasoline is primarily a mixture of hydrocarbons and is sold with an octane rating that is based on a comparison with the combustion properties of isooctane. Gasoline usually contains an isomer of isooctane called tetramethylbutane (C₈H₁₈) , which has an enthalpy of vaporization of 43.3 kJ/mol and a boiling point of 106.5C. Determine the vapor pressure of tetramethylbutane on a very hot summer day when the temperature is 38C.

• A)80.0 torr
• B)36.7 torr
• C)67.8 torr
• D)47.9 torr
• E)89.3 torr

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Definitions:

Archegonium

A female reproductive structure in plants and certain algae, where the egg cell is produced and fertilization occurs.

Charophytes

A group of green algae thought to be the closest relatives of land plants, sharing key traits for terrestrial adaptation.

Desiccation

The process of extreme drying out or dehydration, which can be detrimental to living organisms as it leads to loss of moisture and can disrupt cellular and systemic functions.

Sporophyte

The diploid, spore-producing phase in the life cycle of plants that undergo alternation of generations.