1. CALORIMETRY Calorimetry: measurement of heat changes
The heat transferred is proportional to the
mass of the object (m)
specific heat capacity (Cp)
temperature change (∆T)
Heat has the symbol q and is calculated using
q = m∆TCp

2. Specific heat (s)
amount of heat (q) required to raise the temperature of one gram of the substance by one degree Celsius.
Water

3. Specific heat capacity …
Heat Capacity (Cp)
amount of heat (q) required to raise the temperature of a given quantity (m) of the substance by one degree Celsius.
Specific heat capacity …
…varies from one substance to another
…a measure of how much heat something can “hold”
…the amount of heat needed to raise one gram of a substance by one Celsius degree

4. The specific heat capacity of water is 4.18 J/g∙°C
Quantity of heat
q = mDTCp
The specific heat capacity of water is 4.18 J/g∙°C

5. q = mDT Cp q =(25.6g)(30.0C) (4.18J/gC) q = 3210 J
How much heat is needed to raise the temperature of 25.6 grams of water from 20.0 C to 50.0 C?
q = mDT Cp
q =(25.6g)(30.0C) (4.18J/gC)
q = 3210 J

6. q = mDTCp = q DT mCp Answer: 6.20 °C
What is the final temperature of 27.0 grams of liquid water, initially at 0°C, after it absorbs J of energy?
q = mDTCp
Hint: start by solving for DT. = q DT
mCp
Answer:
6.20 °C

7. Dt = Tfinal – Tinitial = 50°C – 940°C = -890°C
Ex. How much heat is given off when an 869 g iron bar cools from 940°C to 50°C?
s of Fe = J/g • °C
Dt = Tfinal – Tinitial = 50°C – 940°C = -890°C
q = m∆TCp
= 869 g x J/g • °C x –890°C
= -34,000 J