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THEORY OF ATOM
versa. This is a revolutionary discovery of Einstein in the field of science Heat, light, electricity and magnetism are some of the visible forms of energy.
HEAT: We have scen that electrons move within the atom; atoms move within the molecules and the molecules themselves, are also in constant motion in all states of matter This motion of molecules is known as heat or thermal motion and is responsible for the phenomenon of heat
If we boat a substance, the molecular motion becomes more violent, while with cooling, the intensity of the motion subsides. What we usually call temperature is nothing else but a measurement of the degree of molecular agitation
It has been established that at a temperature of 273 degrees C or 459 degrees F, thermal agitation of matter completely ceases and all its molecules come to rest. This temperature is, therefore, known as absolute zero All substances are frozen solid at 'Absolute zero' Hydrogen, oxygen and nitrogen are solid below 259 degrees C, and 218 degrees C and 209 degrees C respectively. Above these temperature they melt and become liquid and at still higher temperatures they boil and become gaseous. Frozen water (ice) melts only at 0 degree C. Leads melts at +327 degrees C, iron at +1535 degrees C and osmium remains solid upto +2700 degrees C In the same way water boils at 100 degrees C while lead boils at + 1620
