Question

6. 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

78.8°C

Step-by-step explanation:

Given parameters:

Amount of heat energy = 130kCal

Mass of the cheese = 2.5kg

Initial temperature = 27°C

Unknown:

Final temperature = ?

Solution:

To solve this problem, use the expression below;

H = m C (T₂ - T₁)

H is the amount of heat

m is the mass

C is the specific heat capacity of water = 4200J/kg°C

Now,

convert the amount of heat to kJ;

1kCal = 4.18KJ

130kCal = 130 x 4.18 = 543.4kJ

Insert the parameters and solve;

543.4 x 10³ = 2.5 x 4200 x (T₂ - 27 )

543.4 x 10³ = 10500 x (T₂ - 27 )

(T₂ - 27 ) = 51.75

T₂ = 51.75 + 27 = 78.8°C