NEET Chemistry Thermodynamics / रासायनिक उष्मागतिकी NEET PYQ-Thermodynamics

In an endothermic reaction, the value of \[\Delta H\] is:                                                       [AIPMT 1999]

A) zero

B) positive

C) negative

D)      constant

Correct Answer: B

Solution :

For endothermic, reactions standard heat of reaction \[(\Delta H)\] is positive because in these total energy of reactant is lower than product. i.e.

\[{{E}_{R}}<{{E}_{P}}\]

So, \[\Delta H={{E}_{P}}-{{E}_{R}}=+ve\]