Question

Please help me slove the blanks please

absorbance	(CrO4)2-	[Ag+]	ksp of Ag2CRO4
0.504
0.506
0.506

Average ksp:

SD:

PLEASE SO CALCULATION.INFORMATION NEED TO Solve this problem would be.

inital[CrO42-]=0.0024M

VOL OF 0.0024M K2CrO4	total vol	Cro4-	absorbance
1ml	100ml	0.000024	0.057
5ml	100ml	0.00012	0.284
10ml	100ml	0.00024	0.432
15ml	100ml	0.00036	0.502

AVG MOLAR ABSORPTION COEFFICEINT:

SD:

Molar absorbtion coefficient [Cro42-]

1.3*10-6cm-1M-1, 2.3*10-5 cm-1M-1, 108*10-5cm-1M-1, 1.8*10-4CM-1M-1

CAN YOU ALSO FIND THE AVERAGE FOR THE MOLAR ABSORPTION COEFFICIENT AND ITS STANTARD DERIVATION.

Answer 1

You know I have doubts with the first chart you are putting, because I don't understand the absorbance you a re putting there. Are those absorbance from the whole Ag₂CrO₄ or the silver?

While you are clearing that to me, I will answer your second part.

You are already giving the molar absorption coefficient, so the average would be:

Avg = 1.3x10^-6 + 2.3x10^-5 + 1.08x10^-5 + 1.8x10^-4 / 4 = 5.3775x10^-5

SD = [(1.3x10^-6 - 5-3775x10^-5)² + (2.3x10^-5 - 5-3775x10^-5)² + (1.08x10^-5 - 5-3775x10^-5)² + (1.8x10^-4 - 5-3775x10^-5)² / 3]^1/2

SD = 8.46x10^-5

Please can you tell me the doubt in the first part, so I can answer it better?.

Ksp = [Ag]² [CrO₄^2-] ----> Ag₂CrO₄ ---------> 2Ag⁺ + CrO₄^2-

So, if you know the concentration of CrO4, you may actually predict the concentration of Ag and then, the ksp. But I need you to tell me, what those values of absorbance means.