How many joules ar required to heat a frozen can of juice (360 grams) from -5 degrees C (the temp of an overcooled refrigerator) to 110 degrees C (the highest practical temp within a microwave oven)?
q1 to raise T from -5 to zero C (I assume most of this is water).
q1 = mass x specific heat x delta T.
q2 = heat to convert solid at zero C to liquid at zero C.
q2 = mass x heat fusion
q3 = heat to raise T from zero C to 100 C.
q3 = mass x specific heat x delta T.
q4 = heat to convert liquid phase at 100 C to vapor phase at 100 C.
q4 = mass x heat vaporization.
q5 = heat to raise T from 100 C for vapor to 110 C for vapor.
q5 = mass x specific heat x delta T.
total q = sum of q1 + q2 + q3 + Q4 + q5
To calculate the amount of energy required to heat a substance, you can use the equation:
Q = m * c * ΔT
Where:
Q is the amount of energy (in joules) required
m is the mass of the substance (in grams)
c is the specific heat capacity of the substance (in J/g°C)
ΔT is the change in temperature (in °C)
First, we need to determine the change in temperature (ΔT) by subtracting the initial temperature from the final temperature:
ΔT = final temperature - initial temperature
ΔT = 110°C - (-5°C)
ΔT = 115°C
Next, we need to determine the specific heat capacity (c) of the frozen juice. The specific heat capacity varies depending on the substance. For water, the specific heat capacity is approximately 4.18 J/g°C. However, the specific heat capacity of frozen juice may be slightly different.
Assuming the specific heat capacity of the frozen juice is also 4.18 J/g°C, we can now calculate the energy required:
Q = m * c * ΔT
Q = 360g * 4.18 J/g°C * 115°C
Calculating this would give you the amount of energy (in joules) required to heat the frozen juice can from -5°C to 110°C.