Lesson 2 A and B
A
- Objects do not contain heat. Objects, which are made of atoms, molecules and ions, contain energy. Heat is the transfer of energy from an object to its surroundings or to an object from its surroundings.
- Heat changes the temperature of an object
- Heat contributes to overall internal energy of an object
- kinetic energy is one of the forms of internal energy, the release of heat from an object causes a decrease in the average kinetic energy of its particles.
- Release of energy does not always cause temperature change
- Heat contributes to the change in the state of a substance
- The removal of heat can change the state of an substance
- The temperature change section occurs when the substance is in-between states
- Energy transfer in the form of heat can result in the performance of work upon the system or its surroundings
- Ex- heat engines
- Specific heat capacity- amount of heat required to cause a unit of mass to change its temperature by 1 degree Celsius
- Gram or kilogram basis
- q=m.c.dt
- q- quantity of heat
- m- mass
- c- specific heat capacity
- Dt- resulting temperature change of the object
- Dt= tfinal-tinital
- Positive Q means that the object increased temperature
- Negative Q means that the object decreased temperature