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2.1 Kinetic particle model of matter

• Define Brownian motion: It is the random movement of larger particles, due to their collision with faster moving, smaller particles.
• Define Absolute scale of temperature: A temperature scale, whose 0⁰C  is  equivalent to -273.15 °C (absolute zero) and whose 373.150C is equivalent to 100⁰C.
• Define Absolute zero:  Absolute zero is the temperature  at which a thermodynamic system has the lowest energy. This temperature corresponds to -273.15⁰C on a Celsius temperature scale.
• State Boyle's law: For a fixed mass of a gas at constant temperature, the volume varies inversely as the pressure. Hence pv=constant; where p=pressure on the gas and v=volume of the gas.

2.2 Thermal properties and temperature

• Define Thermal expansion: Thermal expansion is the expansion of an object under the influence of heat
• Define Specific heat capacity:It is the amount of heat energy , needed to raise the temperature of unit mas of a substance through 1⁰C
• Define Melting point: It is the temperature at which a solid changes into a liquid
• Define Boiling point: It is the temperature at which a liquid changes into a gas, without a rise in temperature.
• Define Evaporation: It is the temperature at which a liquid changes into a gas, over a range of temperatures

2.3 Transfer of thermal energy

• Define Good thermal conductors (bad thermal insulators): Substances that allow the heat energy to flow through them easily are called as good thermal conductors.
• Define Bad thermal conductors ( good thermal insulators):Substances that do not  allow the heat energy to flow through them easily are called as good thermal insulators.
• Define Conduction:Conduction is the  the transfer of energy through the movement of particles that are touching  each other.
• Define Convection:Convection is a process of heat transfer involving density differences within molecules of the same fluid , in which the warmer and less dense portions rise up, while the more dense and the heavier ones sink down.
• Define Radiation:Radiation refers to the process of  transmission or emission of energy in the form of waves that can travel through vacuum, meaning they do not require any medium.

 

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