Question

why is specific heat different for different substances??

Answer 1

In physics , Different substances have different specific heat capacities because some substances, when they take in energy, store it in forms other than molecular kinetic energy

Answer 2

The specific heat of a substance is the amount  of heat required to raise the temperature of unit mass of substance by one unit. The specific heat of a substance  depends on its nature .It gives us an idea of  the degree of 'reluctance' of a substance to change its temperature.We know that the temperature of a body is directly proportional to the average kinetic energy of particles of the body . The heat will be shared by the molecules among the various forms of energy. This sharing of heat energy of the system also varies with temperature . That is why the specific heat is different for different for different substances.                                                                                        

                                               specific heat
Substance                 In cal/g-⁰C            In J/Kg-K                                   
Lead                            0.031                        130
Mercury                       0.033                        139
Brass                          0.092                         380
Zinc                            0.093                         380
Copper                       0.095                          399
Iron                            0.115                          483
Glass(flint)                   0.12                          504
Aluminum                   0.21                           882
Kerosene oil               0.50                           2100
Ice                              0.50                           2100
Water                          1                               4180
Sea water                   0.95                           3900

Hope this helps you ............... :-)