Here was my procedure: Procedure 1: Prove the Law of Mass Conservation 1. Place
ID: 858291 • Letter: H
Question
Here was my procedure:
Procedure 1: Prove the Law of Mass Conservation
1. Place the Erhlenmeyer flasks with 1.00 g AgNO3 and 1.00 g NaCl on the benchtop. Place the distilled water on the benchtop.
2. The solution labeled "1.00 g NaCl" contains 1.00 g of NaCl dissolved in water. Use
the solution viewer to determine the number of grams of Na+ and Cl- in the solution, and confirm that these add to 1.00 g.
3. The solution labeled "1.00 g AgNO3" contains 1.00 g of solid AgNO3. Add 100.0 mL of water to this solution by choosing the "Precise Transfer" mode, input 100.0 mL in the "Transfer Amount" and then "Pour" it into the flask. Use the solution viewer to
determine the number of grams of Ag+ and NO3- in the solution.
Now I need help with these questions.
1. Identify the mass of each reactant ion and the total mass of the reactants.
2. Identify the mass of each product and the total mass of the product.
3. Explain how this experiment confirms the Law of Mass Conservation.
Explanation / Answer
AgNO3 = Ag+ + NO3-
Mass(AgNO3)=1g
Moles(AgNO3)= 1/169.87 = 0.00588
So, 0.00588 moles AgNO3 will dissociate in water into (0.0058moles)Ag+ and (0.0058moles)NO3-
So mass (Ag+) = 0.0058 moles *atomic weight=0.0058*107.86=0.6349g
Mass(NO3)=0.0058 *62.0049=0.36 g
Next,1g NaCl in water
NaCl = Na+ + Cl-
Moles of NaCl = 1/58.44=0.017
They will dissociate into Na+ and Cl- each of 0.017 moles
Mass (Na+)=0.017 *22.98=0.4g
Mass(Cl-)=0.017*35.45=0.6g
When AgNo3 mixed with NaCl,
AgNO3 + NaCl = AgCl +NaNO3
== > [Ag+] +[ NO3-] +[Na+] +[ Cl-] = total mass of reactant
0.6349 +0.36 +0.4+0.6 = 2 g(approx.)
From reaction we know,
Moles(AgNO3)=0.0058
Moles( NaCl) = 0.017
AgNO3 is limiting reactant.
So, moles of AgCl andNaNO3 formed are 0.0058 moles each
Thus, mass(AgCl) =0.0058 moles *143.32=0.831g
Mass(NaNO3)=0.0058*84.99=0.49g
Total mass of product=0.831+0.49=1.321g + remaining mass of Nacl that remained unreacted ie 0.011 moles
1.321+0.644=2g(approx)
Total mass of reactant=2g
The total mass of reactants is always approximately equal to mass of products.this states the law of conservation of mass