The document provides a comprehensive overview of heat and temperature for grade 8 science, explaining the concepts, measurements, and calculations related to thermal energy. Key topics include the difference between heat and temperature, heat capacity, and example problems illustrating specific heat calculations. Prepared by Engr. L.N. Abrigo, the module serves as an educational resource for understanding fundamental principles of heat transfer and temperature dynamics.

1. SCIENCE
Module 3
GRADE 8
Prepared by: Engr. L.N. Abrigo

2. MODULE 3: HEAT AND TEMPERATURE
Lesson 1 – HEAT VS. TEMPERATURE
WHAT IS HEAT?
● Heat is viewed as a form of energy that is
transferred from one body due to a difference in
temperature.
● The SI unit of heat is Joule (J).
● A more common unit is calorie (cal) which is
defined as the amount of heat needed to change
the temperature of one gram of water by 1 degree
celsius ( )
Prepared by: Engr. L.N. Abrigo

3. MODULE 3: HEAT AND TEMPERATURE
Lesson 1 – HEAT VS. TEMPERATURE
WHAT IS TEMPERATURE?
● Temperature is the “hotness” or coldness” of a
substance.
● It is the measure of the motion of the molecules or
atoms within the substance (Particle Theory of
Matter).
● Thus, on the molecular level, temperature is the
measure of the average kinetic energy of the
Prepared by: Engr. L.N. Abrigo

4. MODULE 3: HEAT AND TEMPERATURE
Lesson 1 – HEAT VS. TEMPERATURE
Prepared by: Engr. L.N. Abrigo

5. MODULE 3: HEAT AND TEMPERATURE
Lesson 2 – HEAT EFFECTS ON MATTER (Phase
Change)
PHASES OF MATTER
Prepared by: Engr. L.N. Abrigo

6. MODULE 3: HEAT AND TEMPERATURE
Lesson 2 – EFFECTS ON MATTER (Phase Change)
Prepared by: Engr. L.N. Abrigo

7. MODULE 3: HEAT AND TEMPERATURE
Lesson 3 – HEAT CAPACITY
WHAT IS HEAT CAPACITY?
● the amount of heat needed by a material to
increase its temperature by a degree
Note: What is Thermal/Heat Energy?
-its the energy that is actually contained in an
object due to the motion of its particles
Prepared by: Engr. L.N. Abrigo

8. MODULE 3: HEAT AND TEMPERATURE
Lesson 3 – HEAT CAPACITY
Q = Heat energy
m = mass
c = specific heat
ΔT = change in temperature
= (Tfinal – Tinitial)
Prepared by: Engr. L.N. Abrigo

9. MODULE 3: HEAT AND TEMPERATURE
Lesson 3 – HEAT CAPACITY (SAMPLE PROBLEM)
Question 1: A 500 gram cube of lead is heated from 25 °C to 75 °C. How much
energy was required to heat the lead? The specific heat of lead is 0.129 J/g°C.
Solution: First, let’s the variables we know.
m = 500 grams
c = 0.129 J/g°C
ΔT = (Tfinal – Tinitial) = (75 °C – 25 °C) = 50 °C
Plug these values into the specific heat equation from above.
Q = mcΔT
Q = (500 grams)·(0.129 J/g°C)·(50 °C)
Q = 3225 J
Answer: It took 3225 Joules of energy to heat the lead cube from 25 °C to 75 °C.
Prepared by: Engr. L.N. Abrigo

10. MODULE 3: HEAT AND TEMPERATURE
Lesson 3 – HEAT CAPACITY (SAMPLE PROBLEM)
Question 2: A 25-gram metal ball is heated 200 °C with 2330 Joules of energy. What is the specific heat of
the metal?
Solution: List the information we know.
m = 25 grams
ΔT = 200 °C
Q = 2330 J
Place these into the specific heat equation.
Q = mcΔT
2330 J = (25 g)c(200 °C)
2330 J = (5000 g°C)c
Divide both sides by 5000 g°C
c = 0.466 J/g°C
Answer: The specific heat of the metal is 0.466 J/g°C.
Prepared by: Engr. L.N. Abrigo

11. MODULE 3: HEAT AND TEMPERATURE
Lesson 3 – HEAT CAPACITY (SAMPLE PROBLEM)
Question 2: A 25-gram metal ball is heated 200 °C with 2330 Joules of energy. What is the specific heat of
the metal?
Solution: List the information we know.
m = 25 grams
ΔT = 200 °C
Q = 2330 J
Place these into the specific heat equation.
Q = mcΔT
2330 J = (25 g)c(200 °C)
2330 J = (5000 g°C)c
Divide both sides by 5000 g°C
c = 0.466 J/g°C
Answer: The specific heat of the metal is 0.466 J/g°C.
Prepared by: Engr. L.N. Abrigo

12. MODULE 3: HEAT AND TEMPERATURE
Lesson 4 – TEMPERATURE CONVERSION
Prepared by: Engr. L.N. Abrigo