A slice of pizza has 500 kcal. If we could burn the pizza and use all the heat to warm a 50-L container of cold water, what would be the approximate increase in the temperature of the water? (note; A Liter of cold water weighs about 1 kg) a. 500 C b. 50C c. 10C d.100C
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A slice of pizza has 500 kcal. If we could burn the pizza and use all the heat to warm a 50-L container of cold water, what would be the approximate increase in the temperature of the water?
(note; A Liter of cold water weighs about 1 kg)
a. 500 C
b. 50C
c. 10C
d.100C
The Correct Answer and Explanation is :
To determine the increase in temperature of the 50-L container of cold water when burning a 500 kcal slice of pizza, we use the specific heat capacity formula:
[
Q = mc\Delta T
]
Where:
- ( Q ) is the heat energy in calories (500 kcal = 500,000 cal),
- ( m ) is the mass of the water (50 L × 1 kg/L = 50 kg),
- ( c ) is the specific heat capacity of water (1 cal/g°C = 1 kcal/kg°C),
- ( \Delta T ) is the change in temperature (what we need to find).
Rearranging the formula to solve for ( \Delta T ):
[
\Delta T = \frac{Q}{mc}
]
Substituting the values:
[
\Delta T = \frac{500,000}{50 \times 1}
]
[
\Delta T = \frac{500,000}{50}
]
[
\Delta T = 10°C
]
Thus, the temperature of the water will increase by 10°C, meaning the correct answer is:
c. 10°C
Explanation:
- Understanding the Energy Conversion:
When we burn the pizza, it releases 500 kcal of energy. This energy is absorbed by the 50 kg of water, causing its temperature to rise. - Why Water’s Specific Heat Matters:
Water has a high specific heat capacity (1 kcal/kg°C), meaning it requires a significant amount of energy to change its temperature. - Why Other Answers Are Incorrect:
- 500°C: This would require 25,000 kcal, which is far more than 500 kcal.
- 50°C: This would need 2,500 kcal, still too much energy.
- 100°C: Would need 5,000 kcal, unrealistic for just one slice of pizza.
Therefore, the closest and most accurate answer is 10°C.
Now, I’ll generate an image related to this concept.
Here is an educational illustration showing the concept of burning a slice of pizza to heat a 50-liter container of water by 10°C. Let me know if you need any modifications!