how much energy is required to heat 1.00L of water from 20degrees celcius to 90degress celcius

3 answers

Note the correct spelling of celsius.
q = mass x specific heat x (Tfinal-Tintial)
(Heat in Joules) = (mass in grams) x (specific heat) x (temperature change)

1 L = 1000 grams & specific heat of water = 4.184 J/gram Degree Celsius

Temp Change = 90 - 20 = 70 Deg C

Heat = 1000 g x 4.184 J/g Deg C X 20 Deg C =
83680 J
With 2 significant figures your answer would be 84 kJ
With 3 significant figures your answer would be 83.7 kJ
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