i got the answers right for A B and D but the rest im having difficulties with 2

Question

i got the answers right for A B and D but the rest im having difficulties with

2 Ag+ + Cu --> Cu+2 + 2 Ag
You individually weigh out a piece of Copper Wire and an empty Reaction Tube. You add a measured volume of silver nitrate solution of known concentration to the Reaction Tube and drop in the copper wire.
Weight of copper wire 1.3771 g
Weight of empty Reaction Tube 6.4591 g
Volume of AgNO3 solution used 3.65 mL
Molarity of original AgNO3 solution 0.1536 M

While the silver is being reduced, you make the following spectroscopic measurements. The blank is distilled water. The STANDARD is made by pipetting 1.00 ml of the original standard into a cuvet and adding exactly 5.00 mL of ammonia + distilled water to give a total volume in the cuvet of 6.00 mL.
%T of Blank 99.1 %
Concentration of original Cu Standard 0.0361 M
%T of Cu Standard in cuvet 39.0 %

After the reaction is complete, 2.35 ml of 14 M ammonia is added to the Reaction Tube to give a total of 6.00 mL of blue solution. 1.00 mL is pipetted into the cuvet and 5.00 mL of ammonia and distilled water were added. The %T of this mixed homogeneous solution was measured in the spectrometer.
The mass of the remaining copper wire was measured
The precipitated silver metal in the Reaction Tube was washed with distilled water and dried and the reaction tube with silver crystals was weighed.
%T of Cu ion in Reaction Tube 24.8 %
Mass of Cu Wire after reaction 1.3579 g
Mass of dried Reaction Tube with Silver metal after reaction 6.5240 g
Calculate:
a) Mass of Silver Metal produced ______________ mg
b) Millimoles of Ag + used up ______________ mmol
c) Atomic Weight of Silver based on silver used up ______________ g/mol
d) Mass of Copper Metal lost from wire ______________ mg
e) Atomic Weight of Silver based on copper metal lost ______________ g/mol
f) Absorbance of Cu +2 standard ______________
g) Absorbance of Cu+2 in Reaction Tube ______________
h) Molarity of Cu+2 in Reaction Tube ______________ M
i) Millimole of Cu+2 in Reaction Tube ______________ mmol
j) Atomic Weight of Silver based on Cu+2 produced ______________ g/mol

Explanation / Answer

2 moles of Ag+ reacts with 1 mole of Cu to form 2moles of Ag.

The calculations and solutions are as follows

a) Mass of Silver Metal produced 6.524-6.4591 = 0.0649 g = 64.9 mg
b) Millimoles of Ag + used up 0.1536 M x 1000 x 0.00365 = 0.561 mmol
c) Atomic Weight of Silver based on silver used up 0.0649/5.61 x 10^-4 = 115.69 g/mol
d) Mass of Copper Metal lost from wire 1.3771-1.3579 = 0.0192 g = 19.2 mg
e) Atomic Weight of Silver based on copper metal lost 0.0649 / 0.0192 g x 2 / 63.546 g/mol = 107.40 g/mol
f) Absorbance of Cu +2 standard 2-log(39.0) = 0.409
g) Absorbance of Cu+2 in Reaction Tube2-log(24.8) = 0.606
h) Molarity of Cu+2 in Reaction Tube 1.26 x 10^-5 M
i) Millimole of Cu+2 in Reaction Tube 0.00015 mols = 0.15 mmol
j) Atomic Weight of Silver based on Cu+2 produced = 107.40 g/mol

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