The experiment carried out was a single-replacement reaction between metallic copper atoms (Cu) and an aqueous solution of silver nitrate (AgNO3) (Chemtutor, 2005). The objective was to determine the ratio of reactants to products in the reaction, and the molar ratio between silver (Ag) and copper (Cu) in the reaction.
A clean beaker was weighed, 200 mL of 0.2M silver nitrate solution was added, and the beaker and contents weighed. One gram of copper was then added to the solution. The liquid was decanted and the dry beaker containing the remaining silver was weighed, and the mass of silver obtained calculated. Calculations were performed to determine: a) the mass of copper used in the reaction; b) the moles of copper used in the reaction; c) the mass of silver produced by the reaction; d) and the moles of silver produced by the reaction. The ratio of moles of copper reacted to moles of silver produced was then calculated. A balanced equation for the reaction was written, and calculations made for the same reaction using magnesium in place of the copper to determine how many grams of magnesium would have been used to produce one gram of silver.
Mass of Cu used in reaction = 1 g
Moles of Cu used in reaction, using molar mass
Mass of beaker plus dry Ag =114.815 g
Mass of empty beaker =111.420 g
Mass of Ag produced by reaction = 3.395 g
Moles of Ag produced by reaction, using molar
mass for Ag of 107.9 g/mole = 3.395 moles
Ratio of moles of Cu reacted to moles of AG produced:
=0,0158
i.e. this is roughly a molar ration of 1:2 (one part C
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