Calculate how many joules of energy would be needed to take 2kg of ice at
-5 and turn it all to steam at 100 degees celcius?
first do it all for 1 kg and multiply the answer by 2
-5 to 0
2000 J/kg K * 5 = 10,000 J
melt = 334 *10^3 J = 334,000 J
0 to 100
4190 *100 = 419,000 J
boil = 2256*10^3 = 2,256,000 J
so for 1 kg 3,019,000 J
so for 2 kg 6,038,000 J
To calculate the energy required to convert 2 kg of ice at -5 degrees Celsius to steam at 100 degrees Celsius, we need to consider the different phases of the substance and the energy required for each transition.
The energy required to convert a substance from one phase to another is given by the equation:
Q = m * L
Where:
Q is the energy (in joules) required for the phase change
m is the mass (in kilograms) of the substance
L is the specific latent heat (in joules per kilogram, J/kg) for the specific phase change
In this case, we have three phase changes:
1. Heating the ice from -5 degrees Celsius to 0 degrees Celsius (phase change from solid to liquid)
2. Melting the ice at 0 degrees Celsius to water (phase change from solid to liquid)
3. Heating the water from 0 degrees Celsius to 100 degrees Celsius (phase change from liquid to vapor)
Let's calculate the energy for each phase change:
1. Heating the ice from -5 to 0 degrees Celsius:
The specific heat capacity (c) of ice is approximately 2.09 J/g°C or 2090 J/kg°C.
Using the formula Q = m * c * ΔT, where ΔT is the change in temperature:
Q1 = (2 kg) * (2090 J/kg°C) * (0 - (-5) °C)
= 2 kg * 2090 J/kg°C * 5 °C
= 20,900 J
2. Melting the ice at 0 degrees Celsius to water:
The specific latent heat (L_fusion) for the phase change from solid to liquid is approximately 334,000 J/kg.
Using the formula Q = m * L_fusion:
Q2 = (2 kg) * (334,000 J/kg)
= 668,000 J
3. Heating the water from 0 degrees Celsius to 100 degrees Celsius:
The specific heat capacity of water is approximately 4.18 J/g°C or 4180 J/kg°C.
Using the formula Q = m * c * ΔT, where ΔT is the change in temperature:
Q3 = (2 kg) * (4180 J/kg°C) * (100 - 0) °C
= 836,000 J
Now, let's sum up the energy for each phase change to get the total energy required:
Total energy (Q_total) = Q1 + Q2 + Q3
= 20,900 J + 668,000 J + 836,000 J
= 1,524,900 J
Therefore, approximately 1,524,900 joules of energy are required to convert 2 kg of ice at -5 degrees Celsius to steam at 100 degrees Celsius.