If you add ice to a glass of room-temperature water, does the water warm the ice or
does the ice cool the water? explain.

By the First Law of Thermodynamics heat will flow from the hotter body to the cooler one.  The water warms the ice and in doing so the water gets colder.  

answer: enthalpy

explanation:

for a exothermic reaction, the energy is released i.e. the energy of the products is lower than the energy of the reactants.

= enthaply

= energy of products

= energy of reactants

as , thus comes out to be negative. negative value of enthalpy shows that the reaction is exothermic.

the atomic mass is the bottom number on the element.

-steel jelly