2.Identify the reactant compound in each of the following cases: • CO2 gas is evolved.
• Water vapour is the only gas evolved.
• Two different gases are evolved and the oxide residue remains.​

The characteristics of two different types of reactions are shown below: reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of an element. which statement is true about the atoms of the elements that participate in the two reactions? their identity changes in both reaction a and reaction b. their identity changes in reaction a but not in reaction b. their identity changes in reaction b but not in reaction a. their identity remains the same in both reaction a and reaction b.