Question

For a spontaneous reaction
(A) ΔH = +ve, ΔS = -ve
(B) ΔH = -ve, ΔS = +ve
(C) ΔG = +ve, ΔS = -ve
(D) ΔG = +ve, ΔH = +ve

Answer 1

For a spontaneous reaction

ΔG = ΔH - TΔS

Here, ΔG is the free energy charge, ΔH is the enthalpy, T is the temperature in Kelvin and ΔS will be the change in entropy.

If ΔH = +ve, ΔS = -ve, then ΔG = not –ve at any temp, not spontaneous

If ΔH = -ve, ΔS = +ve, then ΔG = -ve will all temperature

If ΔH = -ve, ΔS = -ve, then ΔG = -ve at low temperature

If ΔH = +ve, ΔS = +ve, then ΔG = -ve at high temperature

Answer 2

Explanation:

with speed u strikes a rod AB of mass M and

length L at the end B and gets embedded into it.

If initially the rod is vertical and hinged at end A,

then angular speed of the system just after

collision will bethe green substance in plants that takes in light from the sun to help them grow

पौधों में पाया जाने वाला हरा पदार्थ जो सूर्य की किरणों को आत्‍मसात कर पौधों की वृद्धि में सहायता करता है; पर्णहरित, क्‍लोरोफ़िल