Question

The nutritional information on a cereal box shows that one serving of dry cereal has 90 calories (actually kilocalories). If one were to burn a serving of cereal, the amount of heat given off would be sufficient to raise the temperature of 1 kg of water how many degrees Celsius?

Answer 1

90 degrees Celsius

Step-by-step explanation:

A calorie is the amount of energy needed to raise the temperature of 1 gram of water 1 degree Celsius.

A kilocalorie is 1000 calories

90kilocalories = 90 x 1000 = 90000 calories

1 kg = 1000 grams

temperature = calories/ grams = 90000/1000 = 90 degrees Celsius

Answer 2

Δt = 90.00 °C

Step-by-step explanation:

The nutritional information on a cereal box shows that one serving of dry cereal has 90 calories (actually kilocalories) so

The amount of heat is 90.00 Kcal

Q= 90000 cal

The mass of water is m = 1 kg = 1000 g

There is a formula that relates the amount of heat, the mass and the temperature variation :

Q = C.m.Δt

Where Q is the amount of heat, m is the mass,Δt is the temperature variation and finally C is the Specific heat (in this case C=Water specific heat)

C(Water) = 1.00 (cal/g.°C)

Q = C.m.Δt

90000 cal = 1.00 (cal/g.°C). 1000 g .Δt

Solving, Δt = 90.00 °C

Be aware of having all in congruent units. Also, we are supposing that water is in solid state.Otherwise, C(Water) ≠ 1.00 (cal/g.°C)