Chemical Thermodynamics Chapter 4 Chemistry Class 12 Textbook Solution
2. Answer the following in one or two
sentences.
iv. What is standard state of a substance?
Answer:-
The standard state of a substance is the form in which the substance is most stable at a pressure of 1 bar and at temperature 298 K . If the reaction involve s species in solution its standard state refers to 1 M concentration. Standard states of certain elements and compounds are H2(g), Hg(l), Na(s) or C(graphite), C2H5OH(l), CaCO3(s), CO2(g) C2H5OH(l), H2O(l), CaCO3(s), CO2(g) refer to 1 bar and 25 0C.