1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Aleks [24]
3 years ago
10

If the molar absorptivity constant for the red dye solution is 5.56×104 M-1cm-1, calculate the molarity of the red dye solution

at the optimal wavelength 519nm and absorbance value 0.945
You may assume L = 1.20cm. Hint: A=εLC

b. Convert the molarity in part a to w/v%. Show your work. Molar mass of FD&C red #3 = 879.86g/mol Refer to examples on next page

c. If you want to dilute the red dye solution in part a by 5 times in a single dilution step, explain in two sentences on how one should proceed with the dilution. In addition, calculate the final concentration of the diluted solution. Show your work for the numerical part of this question.
Chemistry
1 answer:
Shtirlitz [24]3 years ago
8 0

Explanation:

a) Using Beer-Lambert's law :

Formula used :

A=\epsilon \times c\times l

where,

A = absorbance of solution = 0.945

c = concentration of solution = ?

l = length of the cell = 1.20 cm

\epsilon = molar absorptivity of this solution =5.56\times 10^4 M^{-1} cm^{-1}

0.945=5.56\times 10^4 M^{-1} cm^{-1}\times 1.20 \times c

c=1.4163\times 10^{-5} M=14.16 \mu M

(1\mu M=10^{-6} M)

14.16 μM is the molarity of the red dye solution at the optimal wavelength 519nm and absorbance value 0.945.

b) c=1.4163\times 10^{-5} mol/L

1 L of solution contains 1.4163\times 10^{-5} moles of red dye.

Mass of 1.4163\times 10^{-5} moles of red dye:

1.4163\times 10^{-5}\times 879.86g/mol=0.01246 g

(w/v)\%=\frac{\text{Mass of solute (g)}}{\text{Volume of solvent (mL)}}\times 100

red(w/v)\%=\frac{0.01246 g}{1000 mL}\times 100=0.001246\%

c) In order to dilute red dye solution by 5 times, we will need to add 1 L of water to solution of given concentration.

Concentration of red dye solution = c=1.4163\times 10^{-5} M

Concentration of red solution after dilution = c'

c=c'\times 5

1.4163\times 10^{-5} M=c'\times 5

c'=2.83\times 10^{-6} M

The final concentration of the diluted solution is 2.83\times 10^{-6} M

You might be interested in
`You have to be careful about pouring drano down your pipes since it is mainly hydrochloric acid--you can't do it if they are ma
Zanzabum

Answer:

6.67 moles

Explanation:

Given that:-

Moles of hydrogen gas produced = 10.0 moles

According the reaction shown below:-

2Al + 6HCl\rightarrow 2AlCl_3 +3H_2

3 moles of hydrogen gas are produced when 2 moles of aluminium undergoes reaction.

Also,

1 mole of hydrogen gas are produced when \frac{2}{3} moles of aluminium undergoes reaction.

So,

10.0 moles of hydrogen gas are produced when \frac{2}{3}\times 10.0 moles of aluminium undergoes reaction.

<u>Moles of Al needed  = \frac{2}{3}\times 10.0 moles = 6.67 moles</u>

6 0
3 years ago
Periodic table <br> fill in the box :)
Natalija [7]

Answer:

I took a screen shot of your image, and wrote on top of it!

Explanation:

Hope this helps! :)

6 0
2 years ago
Why did workers form labor unions?
USPshnik [31]

Answer:

Labor unions were created in order to help the workers with work-related difficulties such as low pay, unsafe or unsanitary working conditions, long hours, and other situations. ... Sometimes the unions organized strikes in order to try to change the conditions of the workers.

Explanation:

5 0
3 years ago
Read 2 more answers
How much volume (in cm^3)is gained by a person who gains 11.8 lb of our fat? Human fat has a density of 0.918 g/cm^3
Zinaida [17]

The volume (in cm³) gained by a person who gains 11.8 lb of fat is 5830.49 cm³

<h3>What is density? </h3>

The density of a substance is simply defined as the mass of the subtance per unit volume of the substance. Mathematically, it can be expressed as

Density = mass / volume

<h3>How to convert pounds to grams </h3>

1 lb = 453.592 g

Therefore,

11.8 lb = 11.8 × 453.592

11.8 lb = 5352.3856 g

<h3>How to determine the volume </h3>
  • Mass = 5352.3856 g
  • Density = 0.918 g/cm³
  • Volume =?

Volume =  mass / density

Volume =  5352.3856 / 0.918

Volume = 5830.49 cm³

Learn more about density:

brainly.com/question/952755

#SPJ1

3 0
2 years ago
Do you think precipitation has a greater impact on the rate of chemical weathering or mechanical weathering? Explain
nexus9112 [7]

Greater rainfall has an greater increase on the rate of chemical weathering. Rain is a form of precipitation.

6 0
2 years ago
Other questions:
  • Pesticide concentrations in the Rhine River between Germany and France between 1969 and 1975 averaged 0.55 mg/L of hexachloroben
    7·1 answer
  • Computer model that usually shows a process is called
    6·1 answer
  • Main ides what is weather
    9·1 answer
  • Assuming equal concentrations and complete dissociation, rank these aqueous solutions by their freezing points. K2SO4 NH4I CoCl3
    13·1 answer
  • A compound contains sodium, boron, and oxygen. An experimental analysis gave values of 53.976 % sodium and 8.461 % boron, by wei
    5·2 answers
  • A dark grey rock has a mass of 80 grams. When dropped in water, it makes the water level rise from 70 mL to 90 mL. What is the d
    6·2 answers
  • What is 3200000 in scientific notation?
    9·2 answers
  • How do i salve 50,200 mL to L
    5·1 answer
  • How do you get bic grip permanent off of your hands?
    7·2 answers
  • Write the symbol for every chemical element that has atomic number less than 13 and atomic mass greater than 17.2 u.
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!