Which of the following statements is/are correct? 1. spontaneous changes only occur in the direction that leads to equilibrium. 2. exothermic reactions are always spontaneous. 3. in any chemical reaction, energy must be conserved. a. 1 only b. 2 only c. 3 only d. 1 and3 e. 1, 2, and3

Talking about the progress of a chemical reaction all the three statements are correct because;

(1) When a reaction is occurring the spontaneous change occurs in the direction where equilibrium will be achieved.

(2) Exothermic reactions are those in which the release of heat energy happens. And when there is release of energy in a reaction, the reaction will be spontaneous.

(3) In a chemical reaction, law of energy conservation applies, which means the mass of reactant we started with will be equal to the mass of product obtained.

Hence, (d) is the right choice.

water and alcohols have similar properties because water molecules contain hydroxyl groups that can form hydrogen bonds with other water molecules and with alcohol molecules, and likewise alcohol molecules can form hydrogen bonds with other alcohol molecules as well as with water.