Chemical Forums
Chemistry Forums for Students => High School Chemistry Forum => Topic started by: ROxy on November 24, 2004, 08:08:12 PM

What formula do I use if I want to calculate how much energy is absorbed by water?

Q = mc.dT
Q: heat absorbed
m: mass of water
c: specific heat capacity of water
dT: change in temperature

Q = mc.dT
Q: heat absorbed
m: mass of water
c: specific heat capacity of water
dT: change in temperature
Can iuse the same formula to find the amount per gram of fuel burned?

Can iuse the same formula to find the amount per gram of fuel burned?
No

Q = mc.dT is applicable for physical processes. eg. transfer of heat to water.
Q = mc.dT is only applicable for burning fuel for this case:
1. burn 200g of fuel
2. heat evolved is used to heat water
3. all heat evolved from burning fuel channels to the water. [assumption]
4. water remains in liquid state.
heat evolved for burning 200g of fuel
= heat absorbed by water
= mc.dT where m: mass of water, c: specific heat capacity, dT: change in temperature.