Difficulty: Medium

Average Score: 60%

The energy density of a fuel is the amount of useful energy stored in a specific amount of that fuel. The energy density, measured in megajoules per kilogram (MJ/kg), is related to the chemical composition of the fuel.

The chemical composition and energy density of four fuels are shown in the table. Ethane, which has a chemical composition of C2H6, is also a fuel. What is the predicted energy density of ethane?

Rationale

52 MJ/kg

The predicted energy density of ethane (C2H6) is 52 MJ/kg, based on its chemical composition and the typical energy values associated with hydrocarbons of similar structure. Ethane's molecular structure allows for significant energy release during combustion, resulting in a higher energy density compared to some other fuels.

A (45 MJ/kg) YOUR ANSWER

This value is lower than the expected energy density for ethane. Fuels with a similar molecular structure to ethane typically have higher energy densities, and 45 MJ/kg does not align with the known combustion characteristics of ethane.

B (42 MJ/kg) YOUR ANSWER

An energy density of 42 MJ/kg is also considered too low for ethane. This value might be more representative of lighter or less energy-dense fuels, which do not fully account for the energy potential in ethane's molecular structure.

C (52 MJ/kg) CORRECT

This is the correct choice, as ethane's energy density is accurately predicted to be around 52 MJ/kg. This value reflects the energy released during its combustion and is consistent with empirical data for hydrocarbons of its type.

D (48 MJ/kg) YOUR ANSWER

While 48 MJ/kg is a reasonable estimate for some fuels, it is still less than the expected energy density of ethane. Ethane's properties indicate that it should have a higher energy density, making this option inaccurate.

Conclusion

The energy density of a fuel like ethane is determined by its chemical composition and molecular structure. Ethane, with its formula C2H6, exhibits a predicted energy density of 52 MJ/kg, which is in line with the characteristics of hydrocarbons. Other values presented do not reflect the true energy potential of ethane, highlighting the importance of understanding molecular structure in energy predictions.

The chemical composition and energy density of four fuels are shown in the table. Ethane, which has a chemical composition of C2H6, is also a fuel. What is the predicted energy density of ethane?

52 MJ/kg

Related Questions

Related Quizzes

How familiar were you with this question?

Report an Issue

Rate this Practice Test