in chemistry how do you know what the temperature is when you need do find how much energy is released?
Like the formula,Quantity of heat=mass of substance*capacity of heat*change in temperature? Do you assume that it's room temperature?

Question

in chemistry how do you know what the temperature is when you need do find how much energy is released?
Like the formula,Quantity of heat=mass of substance*capacity of heat*change in temperature? Do you assume that it's room temperature?

aaronq · Answer

$\Delta T=T_f-T_i$ refers to the $change$ in temperature of the medium that is absorbing/releasing heat. Most exercises use water. You would need to measure/know the temperature of the water before the experiment occurs (this would be $T_i$) and the temperature of the water when the reaction you're studying goes to completion - this would be $T_f$.