How much energy is needed to boil water?

(4) On May 15, 2012 at 12:03 am Pikuks [0] said:

Some corrections.

That means that requires 4.186 Joules of energy to heat 1 kilogram of water by 1 °C.

Should read as

That means that requires 4.186 Joules of energy to heat 1 gram [not kilogram] of water by 1 °C.

also

(4.18Joule/gram °C) (100g) (100 °C - 20 °C)

Should read as

(4.18Joule/gram °C) (1000g)[not 100g] (100 °C - 20 °C)

(3) On November 21, 2011 at 4:02 pm Deelkar [0] said:

4.18 joules/(g °C) * 1000 g * (100 °C - 20 °C)

4.18 * 1000 * 80 (joules * g * °C /(g °C))

334,400 joules

334.4 kJ

Or with one MJ of energy you can heat about 3 liters of water from 20°C to 100°C

(2) On November 21, 2011 at 3:54 pm Deelkar [0] said:

Sorry but the answer is not correct, the unit is joules not joules/°C

(1) On September 26, 2011 at 1:47 am Gtom123 [1] said:

If you are wondering about the enthalpy of vaporization for water, it's 40.65kJ/mol

meaning to vaporize* 1 mole of 100C water, you would require 40.65kJ to turn it all into steam.

*note not the same as reaching 100C

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