How much heat in joules is needed to raise the temperature

AI Thread Summary
To calculate the heat needed to raise the temperature of 7.0 L of water from 0°C to 78.0°C, the correct answer is 2.28 x 10^6 J. The calculation involves converting the volume of water to grams, using the specific heat capacity of water, and applying the formula for heat transfer. An initial miscalculation was corrected when the user realized they omitted a factor of ten. The discussion highlights the importance of careful unit conversion and calculation in thermodynamics. Overall, the correct approach confirms the heat required for the specified temperature change.
comoore
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Homework Statement


How much heat in joules is needed to raise the temperature of 7.0 L of water from 0°C to 78.0°C? (Hint: Recall the original definition of the liter.)

Homework Equations


How much heat in joules is needed to raise the temperature of 7.5 L of water from 0°C to 87.0°C? (Hint: Recall the original definition of the liter.)
2.73e+06 J

The Attempt at a Solution


I answered 2.28^06 J.
I have actually already asked this question on another forum, and they couldn't figure it out either. Please help.
 
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I think so...

I did 7000 gm x 78 C=546000 calories
546000x4.184j/calorie=2284.5 kj
Then converted kj to j
 
OH. MY. GOSH. I didn't put the 10 in when I answered. The answer is correct. 2.28x10^6 J.
 
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comoore said:
7.0 L of water
comoore said:
7.5 L of water
Better turn off the tap.
 
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