Question

How many kilocalories of energy are needed to raise the temperature of 13 g of alcohol from 11°C to 23°C? (Given: Specific heat of alcohol = 0.588 cal/g°C and 1 kcal = 1000 cal)

A) 0.07 kcal
B) 0.14 kcal
C) 0.21 kcal
D) 0.28 kcal

Answer 1

The energy required to raise the temperature of 13 g of alcohol from 11°C to 23°C is about 0.0917 kcal, which is closest to the option A) 0.07 kcal.

Step-by-step explanation:

To calculate the energy needed to raise the temperature of 13 g of alcohol from 11°C to 23°C, use the formula Q = mcΔT, where Q is the heat energy, m is the mass of the substance, c is the specific heat capacity, and ΔT is the change in temperature (ΔT = final temperature - initial temperature).

Using the provided specific heat of alcohol (0.588 cal/g°C) and the fact that 1 kcal = 1000 cal, we can proceed with the calculation:

• 
  
• Mass m = 13 g
• 
  
• Specific heat c = 0.588 cal/g°C
• 
  
• Change in temperature ΔT = 23°C - 11°C = 12°C

Q = mcΔT = (13 g)(0.588 cal/g°C)(12°C) = 91.728 cal

To convert calories to kilocalories:

Q = 91.728 cal ÷ 1000 cal/kcal = 0.0917 kcal

From the answer options provided:

• 
  
• A) 0.07 kcal
• 
  
• B) 0.14 kcal
• 
  
• C) 0.21 kcal
• 
  
• D) 0.28 kcal

The closest answer to 0.0917 kcal is A) 0.07 kcal.