Question

A serving of Cheez-Its releases 130 kcal (1 kcal = 4.18 kJ) when digested by your body. If this same amount of energy were transferred to 2.5 kg of water at 27˚C, what would the final temperature be?

Answer 1

The final temperature : 78.925°C

Further explanation  

Heat can be calculated using the formula:  

Q = mc∆T  

Q = heat, J  

m = mass, g  

c = specific heat, joules / g ° C  

∆T = temperature difference, ° C / K  

Energy releases = 130 kcal = 130 x 4.18 kJ=543.4 kJ

The final temperature :

$\tt \Delta T=\dfrac{Q}{m.c}\\\\\Delta T=\dfrac{543.4}{2.5\times 4.186~kJ/kg^oC}\\\\\Delta T=51.925^oC$

Final temperature :

ΔT=final-initial

51.925°c=final-27°c

final = 51.925+27=78.925°C