When a solid melts, why does it absorb energy?

In order for the molecules to actually separate from each other, more energy must be added. This energy, called heat of fusion or heat of melting, is absorbed by the particles as potential energy as the solid changes to a liquid. I hope this helps

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Explanation:

If we increase the concentration of one of the reactants; the equilibrium can reduce its concentration by favouring the forwards reaction and producing more of the products. ... The net result of increasing the concentration of the reactants would be the production of more of the products at equilibrium.