Question

Chemical reactions occur when molecules or atoms collide, the bonds between atoms are broken, and new bonds are formed.Breaking the bonds of the reactants requires energy; bond formation releases energy.Which of the following statements regarding energy changes during a reaction are true?a. Decreasing the temperature decreases the kinetic energy of the reactants, and the reaction goes more slowly.b. When the activation energy is low, the reaction rate is slowc. Reactants must collide, with proper orientation, with energy greater than or equal to the activation energy for a reaction to occur.d. Increasing the amount of reactants increases the number of collisions, and the reaction goes faster.e. If the energy of the products is higher than the energy of the reactants, the reaction is exothermicf. The energy of a collision between atoms or molecules must be greater than or equal to the activation energy (Ea) for bonds to be broken.g. The activation energy (Ea) is the energy difference between the energy of the products and the energy of the reactants.

Answer 1

The following statements are true:

(a)Decreasing the temperature decreases the kinetic energy of the reactants and the reaction goes more slowly.

(c)Reactants must collide, with proper orientation, with energy greater than or equal to the activation energy for a reaction to occur.

(d)Increasing the amount of reactants increases the number of collisions, and the reaction goes faster.

(f)The energy of a collision between atoms or molecules must be greater than or equal to the activation energy (Ea) for bonds to be broken

Step-by-step explanation:

Activation energy, Ea, is the minimum amount of energy required to initiate a reaction.If the activation energy is low,the reaction rate is faster, hence statement (b) is false.

The difference between the energy of the reactants and that of the products is called the enthalpy change (ΔH) of the reaction. In exothermic reaction, the products are at lower energy than the reactants. Whereas in the endothermic reaction, the products are at higher energy than the reactants. Hence statement (e) is false.

The activation energy is the energy difference between the energy of the reactants and the energy of the transition state. Hence statement (g) is false.