Questions

Lee Falk

The comma ( , ) is a punctuation mark in English which is most frequently used.

It is perhaps also the most abused and misused punctuation mark among all.

Processes that require or give off heat will be limited to changes of state, known as phase changes, and changes in chemical constitution, or chemical reactions. Changes of state involve a solid melting, a liquid freezing, a liquid boiling or a gas condensing.

An exothermic process is one that gives off heat, which is transferred to the surroundings. An endothermic process is a reaction which heat has to be supplied to the system from the surroundings.

Here in all the given options, heat is taken away from them to change there phase. 

Liquid to Solid --- Freezing

Gas to Liquid --- Condensation

Gas to Solid --- Deposition 

are all examples of exothermic processes.

Energy tranfer takes place either by means of Heat or Work only in Thermodynamics.

Heat :: Heat Energy is defined as Energy that can be transferred due to temperature change.

Whereas

Thermal Energy :: Thermal Energy is the Internal Energy stored in the system maintained at a certain Temperature.

A galvanic cell is also known as voltaic cell provides electrical energy from the chemical energy.