If you use half as many moles of reactant *then:
you'll make twice as much money
the reaction won't happen
the reaction will release half as much heat
the reaction will absorb heat

The reaction will release half as much heat

Explanation:

Because there are less reactants the amount of energy released will decrease. Because the reactants halves the amount of heat released also halves.

the atomic number will stay the same no matter how many electrons it has, so it doesn’t decrease nor increase. it’ll only change with a different number of protons