For a reaction, AH = 176 kJ/mol and A SO = 0.285 kJ/(K•mol). At what temperatures is this reaction spontaneous?
A. At no temperature
B. T< 50 K
C. T>617 K
D. T< 617 K

C. T>617 K

Explanation:

We are given that

We have to find the temperature at which the reaction is spontaneous.

When

Therefore, the reaction is spontaneous at certain range of temperature.

Option A is not true.

When is negative, then  the reaction is spontaneous.

When T<50

Suppose T=49 K

Therefore, .Hence, the  reaction is not spontaneous.

Option B is wrong.

C.T>617K

Suppose T=618 K

Therefore, .Hence, the  reaction is spontaneous.

So, option C is true.

D.T<617 K

Suppose T=616 K

Therefore, .Hence, the  reaction is not spontaneous.

So, option D is not true.

the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.