One gram of anthracite coal gives off 7000. cal when burned. How many joules is this? How many grams of anthracite are required to raise the temp of 4.0 L of water from 20.0 C to 100.0 C? Can you please explain it step by step, Thank you
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1 joule is equal to 0.238902957619 calories.
So 7000cal. = 29300 Joules
1 gram of anthracite made 29300 Joules so we can say 29300Joules/gram of anthracite
Moving to the water, we will find how much energy is actually required to increase the temperature from 20C to 100C.
4L is 4000 grams of water
(100-20) * 4.184 * 4000grams = 1338880 Joules
we can then take the Joules required and divide by the amount of joules given per gram of anthracite:
1338880 Joules / 29300Joules/gram = 45.70grams of anthracite and needed
So 7000cal. = 29300 Joules
1 gram of anthracite made 29300 Joules so we can say 29300Joules/gram of anthracite
Moving to the water, we will find how much energy is actually required to increase the temperature from 20C to 100C.
4L is 4000 grams of water
(100-20) * 4.184 * 4000grams = 1338880 Joules
we can then take the Joules required and divide by the amount of joules given per gram of anthracite:
1338880 Joules / 29300Joules/gram = 45.70grams of anthracite and needed