Define ""point source pollution"" and ""non-point pollution"".

Point source pollution:

 If pollution comes from a fix source then is called point source pollution.It have a specific location where pollution comes.

Ex: Air pollution ,water pollution.

Non point source pollution:

 If pollution comes from number of sources then is called point source pollution.This pollution does not have a specific point of source.

Ex: Spills ,leaks ,Sewage over flow etc.

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.

it should have an internal chamber and two thermometers sticking out of the top. the internal chamber will also be closed off from the outside.