A compound with molecular mass = 292.16 g/mol was dissolved in a 5.000 mL volumetric flask....

Free

60.1K

Verified Solution

Question

Chemistry

A compound with molecular mass = 292.16 g/mol was dissolved in a5.000 mL volumetric flask. A 1.000 mL aliquot was withdrawn, placedin a 10.000 mL flask and diluted to volume. The apparent absorbanceof the diluted solution at 340 nm was 0.827 in a 1.000 cm cuvette.To check for a possible stray light effect, this sample was dilutedby exactly a factor of 2; the apparent absorbance was now 0.421. Areagent blank showed negligible absorbance. The (true) molarabsorptivity at 340 nm = 2.130 x 104 M-1 cm-1.
a) Estimate the stray light in the spectrophotometer.
b) Calculate the concentration of the compound in thecuvette.
c) What mass of the compound was used to make the solution inthe 5.000 mL flask?

Answer & Explanation Solved by verified expert

3.6 Ratings (656 Votes)

a) Stray light in the spectrophotometer = 0.421 - 0.827/2 = 0.0075

b) For the given data

x g of compound in 5 ml gave a solution

1 ml of above solution diluted to 10 ml gave an absorbance = 0.827

concentration of compound = absorbance/molar absorptivity

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â = 0.827/2.130 x 10^4

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â = 3.88 x 10^-5 M

concentration in original 5 ml sample solution = 3.88 x 10^-5 x 10

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â = 3.88 x 10^-4 M

c) Mass of compound used to make 5 ml solution = 3.88 x 10^-4 M x 0.005 L x 292.16 g/mol

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â = 5.67 x 10^-4 g

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â = 0.57 mg

Get Answers to Unlimited Questions

Join us to gain access to millions of questions and expert answers. Enjoy exclusive benefits tailored just for you!

Membership Benefits:

Unlimited Question Access with detailed Answers
Zin AI - 3 Million Words
10 Dall-E 3 Images
20 Plot Generations
Conversation with Dialogue Memory
No Ads, Ever!
Access to Our Best AI Platform: Flex AI - Your personal assistant for all your inquiries!

Become a Member

A compound with molecular mass = 292.16 g/mol was dissolved in a 5.000 mL volumetric flask....

Free

60.1K

Verified Solution

Question

Chemistry

Answer & Explanation Solved by verified expert

Get Answers to Unlimited Questions

Membership Benefits:

Other questions asked by students

Consider these three adaptations: vascular tissue, seeds, flowers. From these three adaptations which one of these...

7. The body cavity found in the trunk is the ____ while the cavity found...

on Pizza You are ordering pizza and you have two choices a slice of pizza...

Find csc if cot 9 csc 0 1 3 O csc 8 3 O csc...

allowsble minimum tak creos for 2018 fassuming no quiche refund caimy 6 Mulcre Choice 5124000...

ACR4.4 (LO 2, 3, 4), AP At June 30, 2022, the end of its most...

pg 3 Required information [The following information applies to the...

S invests $50,000 in an annuity. Upon retirement at age 65, she elects to receive...

Shrewdly designed budgets assist businesses leaders with awareness of expenditures and managing resources. Businesses use...

Traditional Product Costing versus Activity-Based Costing Assume that Panasonic Company has determined its estimated total...

Drongo Corporation's 4-year bonds currently yield 2.8 percent and have an inflation premium of 1.1%....

QUESTION 2 All else equal, fewer compounding periods results in which of the following? lower...