When 2 different kinds of matter make contact, if they react to each other, they simply exchange atoms, not making any new matter in the process, they simply gets turned into something different.
Matter is neither created nor destroyed during a chemical or physical reaction but changes from one form to another, for example when we burn wood this is a chemical reaction by burning the wood we are not destroying it we are just changing it to a different form which is charcoal, also melting ice is a physical reaction here we are changing the ice from solid to liquid (water).
Rutherford, Geiger and Marsden's experiment proved that every atom has a nucleus and that this nucleus is of positive charge and contains the most of the mass of the atom. 0.005% of the volume occupied by the electrons is the volume of the nucleus.
