Here are some disadvantages, is that nitrogen dioxide is a toxic gas and it can still be harmful when ingested by human, also critics of hydrogen fuel cells argue that although these cells do not emit carbon after burning, they give out nitrogen dioxide and other emissions.
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In an endothermic reaction products are <u>HIGHER </u>than reactants in potential energy and <u>LESS </u>stable.
Explanation:
Energy is input into the reaction in an endothermic reaction. This means the products are of a higher energy level than the reactants. Therefore the reaction increases Gibb's free energy and reduces entropy. Remember in thermodynamic stability involves an increase in entropy and a decrease in Gibbs free energy. Therefore the products are less stable than the reactants. This is why endothermic reactions do not occur spontaneously like exothermic reactions.