Heat is added to a 200.-gram sample of H2O(s) to melt the sample at 0°C. Then the resulting H2O (image) is heated to a final temperature of 65°C. Determine the total amount of heat required to completely melt the sample.
You are given
200 grams of H2O(s) at an initial temperature of 0°C. you are also given the
final temperature of water after heating at 65°C. You are required to get the
total amount of heat to melt the sample. The specific heat capacity, cp, of
water is 4.186 J/g-°C. Let us say that T1 = 0°C and T2 = 65°C. The equation for
heat, Q, is
Q = m(cp)(T2-T1)
Q = 200g(4.186
J/g-°C )(65°C - 0°C)
Q =
54,418J
Answer: 54.418 kJ amount of heat required to completely melt the sample.
Explanation:
Mass of water = 200 g
Initial temperature of the water = 0°C
Final temperature of the water = 65°C
Temperature change =\(\Delta T=65^oC-0^oC=65^oC\)
Specific heat capacity = \(4.186J/g^oC\)
\(Q=mC\Delta T=200 g\times 4.186J/g^oC\times 65^oC\)
\(Q=54,418 J=54.418 kJ\) (1 kJ = 1000J)
54.418 kJ amount of heat required to completely melt the sample.