What happens to the energy released by an exothermic reaction
1) it increases the bond energy of the reactants
2) it raises the temperature of the products
3) it is released into the surroundings
it raises the temperature of the reactants

If the energy is released by exothermic reaction, 3) it is released into surroundings; and it raises the products temperature.

An exothermic reaction is that chemical reaction where the heat is produced and released to the surrounding during the chemical reaction. The products are warmer than the reactants due to the raise in temperature (due to heat). In this reaction, the heat produced is released to the surrounding to attain the thermal equilibrium condition.

The net enthalpy in endothermic is positive whereas in exothermic reaction it is negative. The change in energy is measured using calorimeter.  

b.final

ca has a crystalline lattice with positive ions (since it is a metal, metals are positively charged) and electrons flow freely in its structure since the ca atoms have a large nuclear radius so the electrons are not tightly held, therefore the electrons can flow freely since they are not being highly attracted by the nucleus. moreover, one of the properties of metals are that they are conductors of electricity, thus proving ca is the element.