🌡️ Thermal Properties of Matter
Complete Chapter Notes
1. Heat and Temperature
Heat: Form of energy that flows from higher temperature to lower temperature.
Temperature: Measure of hotness or coldness of a body.
Heat Unit: Joule (J)
Temperature Units: Kelvin (K), Celsius (°C)
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Temperature Units: Kelvin (K), Celsius (°C)
2. Thermal Expansion
Increase in dimensions of a body due to rise in temperature.
Types:
- Linear Expansion: Change in length
- Area Expansion: Change in area
- Volume Expansion: Change in volume
ΔL = αLΔT
ΔV = γVΔT
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ΔV = γVΔT
3. Thermal Expansion of Solids, Liquids & Gases
- Solids: Small expansion
- Liquids: More than solids
- Gases: Maximum expansion
4. Anomalous Expansion of Water
Water behaves abnormally between 0°C to 4°C.
- Water contracts when heated from 0°C to 4°C
- Density is maximum at 4°C
5. Specific Heat Capacity
Amount of heat required to raise temperature of unit mass by 1°C.
Q = mcΔT
- Unit: J/kg·K
6. Cp and Cv
- Cp: Specific heat at constant pressure
- Cv: Specific heat at constant volume
Cp > Cv
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7. Calorimetry
Principle: Heat lost = Heat gained
m₁c₁(T₁ - T) = m₂c₂(T - T₂)
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8. Change of State & Latent Heat
Change of state occurs without change in temperature.
Q = mL
- Latent heat of fusion
- Latent heat of vaporization
9. Heat Transfer
(A) Conduction
Heat transfer without movement of particles.
(B) Convection
Heat transfer with movement of fluid.
(C) Radiation
Heat transfer without medium.
---10. Thermal Conductivity
Q = kA(ΔT / L)
- k = thermal conductivity
11. Blackbody Radiation
Blackbody absorbs all radiation falling on it.
---12. Wien’s Displacement Law
λmax × T = constant
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13. Stefan’s Law
E ∝ T⁴
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14. Important Points
- Heat is energy, temperature is measure
- Water shows anomalous behavior
- Cp always greater than Cv
- Radiation does not need medium
- Blackbody is perfect absorber
