2. USE THE EQUATION Q = MC ΔT
q = change in heat or energy (J)
m = mass (g)
c = specific heat (J/g K)
●
ΔT = change in temperature (K)
3. BOMB CALORIMETRY
The specific heat
used will be that of
water (about 4.184
J/g °C) because the
reaction to find q
will take place in a
bomb calorimeter
like the one pictured
here
4. BOMB CALORIMETRY
The food is placed in the steel
“bomb” where it is combusted
The ignition unit causes the
combustion to occur within the
bomb by heating up the sample
The thermometer measures the
temperature increase as the
reaction within the bomb occurs,
the water absorbing the heat that
is released
The stirrer ensures that the
water’s temperature is staying
the same within the dewar
5. USE THE EQUATION Q = MC ΔT
Ifasked to find the calories in the food
(rather than Joules), convert q to
calories by dividing the number of
Joules by 4.184
The answer is generally in the form of
J/g, kJ/g, J g/mol, kJ g/mol, cal/g, kcal/
● ●
g, etc.
*** 1 cal = 4.184 J ***