If a neuronal membrane, which is normally slightly passively permeable to K+, becomes impermeable, but the Na+/K+-ATPase remains active, the neuron's resting potential would become: more negative, because [K+] increases inside the neuron more negative, because [K+] increases outside the neuron more positive, because [K+] increases inside the neuron more positive, because [K+] increases outside the neuron

Answer : The correct option is, (a) -20 kJ

Explanation :

Endothermic reaction : It is defined as the chemical reaction in which the energy is absorbed from the surrounding.

In the endothermic reaction, the energy of reactant are less than the energy of product.

Exothermic reaction : It is defined as the chemical reaction in which the energy is released into the surrounding.

In the exothermic reaction, the energy of reactant are more than the energy of product.

Enthalpy change : It is the difference between the energy of product and the reactant. It is represented as .

In an endothermic reaction, the energy of products are higher than the reactants energy. Thus, the change in enthalpy is positive.

In an exothermic reaction, the energy of products are lesser than the reactants energy. Thus, the change in enthalpy is negative.

From the given energy diagram we conclude that this is an exothermic reaction diagram.

Thus, the enthalpy of reaction is, -20 kJ