thermodynamics

• Molecular kinetic theory model: Brownian motion is the random motion of larger particles in a fluid caused by collisions with surrounding particles, and can be observed through looking at smoke particles under a microscope. Brownian motion contributed to the evidence for the existence of atoms and molecules.
• You can use a simple molecular model to explain each of the gas laws: ● Boyle’s law - Pressure is inversely proportional to volume at constant temperature E.g If you increase the volume of a fixed mass of gas, its molecules will move further apart so collisions will be less frequent therefore pressure decreases.
• You can use a simple molecular model to explain each of the gas laws: ● Charles’s law - Volume is directly proportional to temperature at constant pressure When the temperature of a gas is increased, its molecules gain kinetic energy meaning they will move more quickly and because pressure is kept constant (therefore frequency of collisions is constant) the molecules move further apart and volume is increased.
• ● Pressure Law - Pressure is directly proportional to temperature at constant volume When the temperature of a gas is increased, its molecules gain kinetic energy meaning they will move more quickly, as volume is constant the frequency of collisions between molecules and their container increases and they collide at higher speeds therefore pressure is increased.
• The specific heat capacity of a substance is the amount of energy required to increase the temperature of 1 kg of a substance by 1 °C/1 K, without changing its state. You can measure the amount of energy required to change the state of a substance using the following formula: Q=ml Where Q is energy required and l is the specific latent heat.
• Ideal gases

  
• isothermal process: It is defined as one in which the temperature of the system remains constant, during the change from its initial to final states.
• Adiabatic process: It is def’ined as one in which there is no exchange of heat (q) between the system and surrounding during operations.
• Isobaric process: It is defined as one in which the pressure of the system remains constant during its change from the initial to final state.
• Isochoric process: It is defined as one in which the volume of system remains constant during its change from initial to final state of the process.
• The Specific Heat (or specific heat capacity, c) of a substance is the quantity of heat required to change the temperature of a unit mass of the substance by one degree Celsius or equivalently by one kelvin.If a quantity of heat ∆Q is required to produce a temperature change ∆T in a mass m of substance, then the specific heat is Q=mc{T where, Q=heat energy, m=mass, c=specific heat capacity, {T=change in temprature.

  In the SI, c has the unit J/kg·K, which is equivalent to J/kg·°C
• Calorimetry Problems involve the sharing of thermal energy among initially hot objects and cold objects. Since energy must be conserved, one can write the following equation:

  Sum of heat changes for all object = 0

  Here the heat flowing out of the high temperature system (ΔQout<0) numerically equals the heat flowing into the low temperature system

  (ΔQin>0) and so the sum is zero. This, of course, assumes that no thermal energy is otherwise lost from the system.