To answer the question, let's first look at the specific heat capacities of benzene and methyl alcohol.
- Benzene (C6H6) has a specific heat capacity of approximately 1.74 J/g°C.
- Methyl alcohol (methanol, CH3OH) has a specific heat capacity of approximately 2.51 J/g°C.
Now, we need to compare the amount of energy required to raise the temperature of 1 kg (1000 g) of each substance by 5 degrees Celsius.
Energy Calculation
For benzene:
- Energy (Q) = mass (m) × specific heat (c) × temperature change (ΔT)
- \( Q_{benzene} = 1000 , \text{g} \times 1.74 , \text{J/g°C} \times 5 , \text{°C} \)
- \( Q_{benzene} = 8700 , \text{J} \)
For methyl alcohol:
- \( Q_{methanol} = 1000 , \text{g} \times 2.51 , \text{J/g°C} \times 5 , \text{°C} \)
- \( Q_{methanol} = 12550 , \text{J} \)
Comparison
From the calculations:
- Energy required for benzene: 8700 J
- Energy required for methyl alcohol: 12550 J
Now let's analyze the answer choices based on this information:
A) It would take more energy to increase the temperature of benzene.
(This is false because it takes less energy to heat benzene compared to methyl alcohol.)
B) Both would require much more energy than a kg of water to increase.
(This is somewhat misleading as water has a specific heat of 4.18 J/g°C. Even though both substances require more energy than benzene to raise the same mass, it's an incorrect comparison with water.)
C) Neither can increase temperature unless they change to a solid state first.
(This is incorrect as both substances can increase in temperature without changing their state.)
D) It would take more energy to increase the temperature of methyl alcohol.
(This is true because 12550 J for methanol is more than 8700 J for benzene.)
Conclusion
The correct answer is D) It would take more energy to increase the temperature of methyl alcohol.
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