The atomic number equals the charge on the nucleus. It therefore also equals the number of protons in the nucleus and also equals numerically the number of electrons in the neutral atom. The atomic number has the symbol Z.
From the equation of the reaction; for every 1 mole of copper, the reaction uses 2 moles of silver nitrate.
<h3>What is a reaction?</h3>
A chemical reaction involves the transformation of one chemical specie into another. The reaction is not shown here hence the question is incomplete.
However, the reaction should be of the sort; Cu + 2AgNO3 ---> Cu(NO3)2 + Cu. Thus, for every 1 mole of copper, the reaction uses 2 moles of silver nitrate.