Using this reversible reaction, answer the questions below: N2O4 2NO2 (colorless) (reddish-brown) - As the temperature increased, what happened to the N2O4 concentration? - Was the formation of reactants or products favored by the addition of heat? - Which reaction is exothermic? Right to left or left to right? - If the change of enthalpy of this reaction when proceeding left to right is 14 kcal, which chemical equation is correct? N2O4 2NO2 + 14 kcal N2O4 2NO2, HR = + 14 kcal N2O4 + 14 kcal 2NO2 N2O4 2NO2, HR = - 14 kcal

1) As the temperature increased what happened to the N2O4 concentration, it decreased

2) Formation of products, products are the right hand side of the equation.

3) Right to left is exothermic

4) Change in enthalpy N2O4 ⇔2NO2, HR = - 14 kcal

As it's an exothermic reaction, the enthalpy of the reactants is higher than the products and the sign of the HR will be negative.

Explanation:

N2O4 ⇔2NO2

(colorless) (reddish-brown)

1) As the temperature increased what happened to the N2O4 concentration, it decreased

2) Formation of products, products are the right hand side of the equation.

3) Right to left is exothermic

4) Change in enthalpy N2O4 ⇔2NO2, HR = - 14 kcal

As it's an exothermic reaction, the enthalpy of the reactants is higher than the products and the sign of the HR will be negative.

Answer to question 1.

The concentration of N2O4 will decrease as the temperature of the system increase.

Explanation:

The formation of N2O4 is an exothermic reaction. It means when NO2 converts into N2O4 during a chemical reaction, certain amount of heat is released.

Hence as the temperate of the reaction increases, the reaction moves towards the forward reaction to minimize the effect of temperature change of system.

The formation of NO2 is an endothermic reaction.

Answer to the question 2.

Reaction:

N2O4 ⇄ 2NO2

In case of temperature increases, the formation of products will be favored.

Explanation:

The forward reaction is favored by heat addition and the product is NO2.

Endothermic reaction is a type of reaction in which energy in the form of heat is added to the reaction to proceed.

In this reaction forward reaction is forward while reverse is a type of exothermic reaction.

Increasing temperature means addition of heat and the reaction will shifts towards forward reaction making more product.

Answer to question 3:

The reaction in which colorless N2O4 is produced is exothermic reaction.

Explanation:

A type of reaction in which heat energy is released as the products are formed from the reactants, is known as the exothermic reaction.

Reaction given in question:

N2O4 ⇄ 2NO2

According to above given reaction, the reverse reaction is the exothermic reaction.

2NO2 → N2O4

In reverse reaction, colorless N2O4 is produced from the reddish brown NO2.

Answer to question 4:

The direction of exothermic reaction is right to left.

Explanation:

N2O4 ⇄ 2NO2

A reversible reaction is a reaction in which the reaction proceeds in both directions, from left to right and right to left.

The reaction proceeding in left to right direction is known as forward reaction while reaction proceeding in right to left is known as reverse reaction.

Hence in this reaction, the reaction moving from right to left is exothermic reaction.

Answer to question 5:

The correct answer is option D which is N2O4 → 2NO2, HR = - 14 kcal.

Explanation: The heat of reaction or the enthalpy difference is the difference in the enthalpies of reactants and products. The given reaction is a exothermic reaction. In exothermic reactions, the enthalpy of the reactants is higher than the products and the sign of the HR will be negative. Hence in last option, energy is given at the product side and have a negative sign showing the reaction is exothermic reaction.