Question

In the equation for an endothermic reaction, the word "heat" appears

a. on the right side

b. on the left side

c. on both sides

d. on neither side

Answer 1

In an endothermic reaction, the word 'heat' appears on the left side of the equation, indicating that heat is absorbed by the system from the surroundings, and energy is required for the reaction to proceed.

Step-by-step explanation:

In an endothermic reaction, energy in the form of heat is absorbed from the surroundings into the system. So, in the equation for an endothermic reaction, the word "heat" appears on the left side as a reactant. This means that the reaction requires an input of energy to proceed, and the system gains energy, leading to an increase in its enthalpy, represented by a positive ΔH (change in enthalpy).

On the other hand, in an exothermic reaction, energy is released into the surroundings as heat, and in the reaction equation, heat would be written on the right side, indicating that it is a product of the reaction. During an exothermic process, the system loses energy, resulting in a decrease in the system's enthalpy, with a negative ΔH value.

Answer 2

In an endothermic reaction, the word 'heat' appears on the left side of the equation as the system absorbs heat, and enthalpy increases. The correct option is b.

Step-by-step explanation:

In an endothermic reaction, heat is absorbed from the surroundings into the system. Therefore, in the chemical equation for an endothermic reaction, the word "heat" would appear on the left side of the equation, indicating that it is a reactant. This is because endothermic reactions require energy input to proceed, and the heat energy is absorbed by the reaction. The enthalpy of the system increases, which is represented as ΔH being positive.

Hence, b is the correct option.