Covalent bonds are formed when electrons are shared between elements that are nonmetals. The ammonium ion, NH+4 , would have covalent bonds because both nitrogen and hydrogen are nonmetals. ... So, the bond between this particular hydrogen atom and the central nitrogen is a dative covalent bond.
Effect of increasing surface area on the rate of a reaction. ... Increasing the surface area of a solid reactant exposes more of its particles to attack. This results in an increased chance of collisions between reactant particles, so there are more collisions in any given time and the rate of reaction increases.
Rock and sand are non-living. All organisms are living.