The Precipitation Reaction of Sodium Chloride with Silver Nitrate: A Step-by-Step Calculation
When sodium chloride (NaCl) reacts with silver nitrate (AgNO?), silver chloride (AgCl) precipitates. This process follows a strict stoichiometry that can be quantitatively analyzed. In this article, we will walk through the steps to determine the mass of AgCl produced when 135 grams of AgNO? reacts with an excess of NaCl.
Understanding the Reaction
The chemical reaction between sodium chloride (NaCl) and silver nitrate (AgNO?) can be represented by the following balanced equation:
[ text{NaCl} text{AgNO}_3 rightarrow text{AgCl} text{NaNO}_3 ]
From the balanced equation, it is clear that one mole of NaCl reacts with one mole of AgNO? to produce one mole of AgCl. This relationship is crucial for our calculation.
Step-by-Step Calculation
Step 1: Writing the Balanced Chemical Equation
The balanced chemical equation for the reaction is:
[ text{NaCl} text{AgNO}_3 rightarrow text{AgCl} text{NaNO}_3 ]
Step 2: Calculating the Molar Mass of AgNO?
The molar mass of AgNO? is calculated as follows:
[ text{Molar mass of AgNO}_3 107.87 , text{g/mol (Silver)} 14.01 , text{g/mol (Nitrogen)} 3 times 16.00 , text{g/mol (Oxygen)} ] [ text{Molar mass of AgNO}_3 107.87 14.01 48.00 170.88 , text{g/mol} ]
Step 3: Converting Grams of AgNO? to Moles
The amount of moles of AgNO? in 135 grams can be calculated as:
[ text{Moles of AgNO}_3 frac{135 , text{g}}{170.88 , text{g/mol}} approx 0.794 , text{moles} ]
Step 4: Using the Stoichiometry of the Reaction
From the balanced equation, we know that 1 mole of AgNO? produces 1 mole of AgCl. Therefore, the moles of AgCl produced will also be approximately 0.794 moles.
Step 5: Calculating the Mass of AgCl Produced
The molar mass of AgCl can be calculated as follows:
[ text{Molar mass of AgCl} 107.87 , text{g/mol (Silver)} 35.45 , text{g/mol (Chlorine)} 143.32 , text{g/mol} ]
Now, the mass of AgCl produced can be calculated as:
[ text{Mass of AgCl} 0.794 , text{moles} times 143.32 , text{g/mol} approx 113.49 , text{g} ]
Final Answer
The mass of AgCl produced from 135 grams of AgNO? is approximately 113.49 grams.
Alternative Calculations
Another approach to solving this problem involves directly using the stoichiometric relationship:
[ 135 , text{g AgNO}_3 times frac{1 , text{mol AgNO}_3}{170 , text{g AgNO}_3} times frac{143.5 , text{g AgCl}}{1 , text{mol AgCl}} 114 , text{g AgCl} ]
This confirms our earlier calculation, showing that 135 grams of AgNO? will produce approximately 114 grams of AgCl.
Understanding Stoichiometry
Stoichiometry is central to understanding chemical reactions and predicting the amounts of reactants and products. The balanced chemical equation and the molar masses are the key tools for such calculations. By mastering these concepts, you can solve a wide variety of chemical reaction problems effectively.