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1.
I am doing step number 9 to determine the limiting reactant for this lab.
http://www.lahc.edu/classes/chemistry/arias/Exp%204%20-%20Limiting%20RF11.pdf
Basically I have two vials labeled A and B filled with filtrate that is yellow.
For vial A, I added 10 drops of 0.2 M K2CrO4, but nothing happened. The color stayed the same.
For vial B, I added 10 drops of 0.1 M AgNO3, and the whole thing turned red.
I am thinking since AgNO3 made the filtrate turn red then it is the limiting reactant, but I am not sure.
Can somebody help me?
Furthermore, when I do the math the grams of AgNO3 is always bigger than K2CrO4.
I am wondering if it is possible for the limiting reactant to weigh more (in grams) than the excess reactant?
3.
Finding the weight of the limiting and excess reactant:
The precipitate (Ag2CrO4) that forms weights 0.193 g and the moles are 5.82 x 10^-4 mol.
Finding for mass for AgNO3:
(5.82 x 10^-4 mol Ag2CrO4) (2 mol AgNO3 / 1 mol Ag2CrO4) (169.872 g AgNO3 / 1 mol AgNO3)
= 0.198 g AgNO3
Finding for mass for K2CrO4:
(5.82 x 10^-4 mol Ag2CrO4) (1 mol K2CrO4 / 1 mol Ag2CrO4) (194.188 g K2CrO4 / 1 mol K2CrO4)
= 0.113 g K2CrO4
AgNO3 always comes out bigger than K2CrO4. So is it possible for AgNO3 to be the limiting reactant?
I am doing step number 9 to determine the limiting reactant for this lab.
http://www.lahc.edu/classes/chemistry/arias/Exp%204%20-%20Limiting%20RF11.pdf
Basically I have two vials labeled A and B filled with filtrate that is yellow.
For vial A, I added 10 drops of 0.2 M K2CrO4, but nothing happened. The color stayed the same.
For vial B, I added 10 drops of 0.1 M AgNO3, and the whole thing turned red.
I am thinking since AgNO3 made the filtrate turn red then it is the limiting reactant, but I am not sure.
Can somebody help me?
Furthermore, when I do the math the grams of AgNO3 is always bigger than K2CrO4.
I am wondering if it is possible for the limiting reactant to weigh more (in grams) than the excess reactant?
Homework Equations
3.
Finding the weight of the limiting and excess reactant:
The precipitate (Ag2CrO4) that forms weights 0.193 g and the moles are 5.82 x 10^-4 mol.
Finding for mass for AgNO3:
(5.82 x 10^-4 mol Ag2CrO4) (2 mol AgNO3 / 1 mol Ag2CrO4) (169.872 g AgNO3 / 1 mol AgNO3)
= 0.198 g AgNO3
Finding for mass for K2CrO4:
(5.82 x 10^-4 mol Ag2CrO4) (1 mol K2CrO4 / 1 mol Ag2CrO4) (194.188 g K2CrO4 / 1 mol K2CrO4)
= 0.113 g K2CrO4
AgNO3 always comes out bigger than K2CrO4. So is it possible for AgNO3 to be the limiting reactant?