How many joules does it take to change 127 grams of water from -15 degrees Celsius to boiling?

Sagot :

4 steps here. 

1. Energy to heat ice from -15 to 0 degrees.
[tex]q_1=m c \Delta T = 127\times 2.09\times 15 = 3981,45[/tex]

2. Energy to convert ice to water.
[tex]q_2=m\Delta H_f = 127 \times 334 = 42418[/tex]

3. Energy to heat water to 100 degrees.
[tex]q_3=m c \Delta T = 127\times 4.18 \times 100 = 53036[/tex]

4. Energy to convert water to steam.
[tex]q_4=m\Delta H_v = 127 \times 2257 = 286639[/tex]

So the total energy is about q_1+q_2+q_3+q_4 = 386074,45 J