answer.
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
yaroslaw [1]
2 years ago
4

The molar absorptivities of tryptophan and tyrosine at 240 nm are 2.00 x 103 dm3 mol-1 cm-1 and 1.12 x 104 dm3 mol-1 cm-1. At 28

0 nm, they are 5.40 x 103 dm3 mol-1 cm-1 and 1.50 x 103 dm3 mol-1 cm-1. A solution of the two has absorbances of 0.660 at 240 nm and 0.221 at 280 nm in a 1.0 cm thick cell. What are the concentrations of these two amino acids in this solution?
Chemistry
1 answer:
padilas [110]2 years ago
5 0

Explanation:

Let us assume that the molar concentrations of tryptophan and tyrosine be x and y respectively.

Mathematically,        A = \epsilon \times t \times C

where,     A = absorbance

             \epsilon = molar absorption coefficient

                t = thickness of the cell

                C = molar concentration

So, first calculate the molar concentration of tryptophan at 240 nm as follows.

            0.66 = 2000 \times 1 \times x + 11200 \times 1 \times y

              x = \frac{0.66 - 11200y}{2000}  ........... (1)

At 280 nm,

            0.221 = 5400 \times 1 \times x + 1500 \times 1 \times y

            0.221 = 5400x + 1500y  ........... (2)

Now, we will substitute the value of x from equation (1) into equation (2) as follows.

         0.221 = 5400 \times \frac{0.66 - 11200y}{2000} + 1500y

         0.221 = 1.782 - 30240y + 1500y

         0.221 = 1.782 - 28740y

         28740y = 1.561

            y = 54.3 \times 10^{-6} M

or,            = 54.3 \mu M ............ (3)

Hence, the molar concentration of tyrosine is 54.3 \mu M and putting this value into equation (1) we will get the value for concentration of tryptophan as follows.

              x = \frac{0.66 - 11200 \times 54.3 \times 10^{-6}}{2000}

                 = 25.8 \times 10^{-6}

or,              = 25.8 \mu M

Therefore, we can conclude that the concentration of tryptophan is 25.8 \mu M and concentration of tyrosine is 54.3 \mu M.

You might be interested in
A molecular biologist measures the mass of Cofactor A in an average yeast cell. The mass is 77.91pg. What is the total mass in m
Anni [7]
In this question, you are given the average cofactor mass per cell (77.91pg) and the total cells count(10^5 cells). You are asked how much cofactor that will be found from those cells(microgram= 10^6 picogram). Then the calculation would be:
Cofactor mass= cofactor per cell * cell count= 77.91pg/cell * 10^5 cells= 7.791 x 10^6pg

Then convert the picogram(pg) into microgram: 7.791x 10^6pg/ (10^6pg/microgram)= 7.791 microgram
8 0
2 years ago
A piece of wire contains 1.52x10^22 atoms of copper. Calculate the miles of copper in the wire
melamori03 [73]

Moles of Copper =

1.52×10^{22}atoms×\frac{1 mol }{6.022 * 10^{23}atoms}

= 0.0252 mol Cu

6 0
2 years ago
A gas of 190 mL at a pressure of 74 atm can be expected to change its pressure when its volume changes to 30.0 mL. Express its n
kozerog [31]

Answer : The new pressure of the gas will be, 468.66 atm

Explanation :

Boyle's Law : This law states that pressure of the gas is inversely proportional to the volume of the gas at constant temperature and number of moles.

P\propto \frac{1}{V}     (At constant temperature and number of moles)

or,

P_1V_1=P_2V_2

where,

P_1 = initial pressure of the gas = 74 atm

P_2 = final pressure of the gas = ?

V_1 = initial volume of the gas = 190 ml

V_2 = final volume of the gas = 30 ml

Now we put all the given values in the above formula, we get the final or new pressure of the gas.

74atm\times 190ml=P_2\times 30ml

P_2=468.66atm

Therefore, the new pressure of the gas will be, 468.66 atm

4 0
2 years ago
Read 2 more answers
A sample of gasoline contains various hydrocarbons, which comprise atoms of carbon, hydrogen, and oxygen. The hydrocarbons mix t
Naddika [18.5K]

Answer:

  • mixture
  • homogenous mixture  (of hydrocarbons)
  • compound

Explanation:

Mixture can be easily separated by physical methods. Homogeneity and heterogeneity of a mixture is determined by whether the components there in are in a single phase and evenly distributed or not.

A solution has a solute evenly dissolved in  solvent to form a liquid substance.

An element is the basic form of  substance which cannot be broke down into any other simpler unit.  

I hope this was helpful.

4 0
2 years ago
When 24 mol of methanol and 15 mol of oxygen combine in the combustion reaction, 2 ch3oh(
umka21 [38]
The balanced equation for combustion is as follows;
2CH₃OH + 3O₂ ---> 2CO₂ + 4H₂O
The stoichiometry of CH₃OH to O₂ is 2:3
the limiting reagent is the reactant that is fully consumed during the reaction. The amount of product formed is directly proportional to the amount of limiting reactant produced. The excess reagent is the reactant that is provided in excess and is not fully used up, there will be an amount of this reagent remaining after the reaction.
If methanol is the limiting reactant,
If 2 mol of methanol reacts with 3 moles of O₂
Then 24 mol of methanol reacts with - 3/2 x 24 = 36 mol of O₂ should be present
But only 15 mol of O₂ is present, therefore O₂ is the limiting reactant and methanol is in excess.
3 mol of O₂ reacts with 2 mol of CH₃OH 
then 15 mol of O₂ reacts with 2/3 x 15 = 10 mol of CH₃OH

Excess reactant is methanol, 10 mol are used up therefore 24 - 10 mol = 14 mol are remaining at the end of the reaction 
8 0
2 years ago
Other questions:
  • A bird building a nest for its young is a reproductive strategy. Based on this example, what do you think the term “reproductive
    6·2 answers
  • The molecular weight of table salt, NaCl, is 58.5 g/mol. A tablespoon of salt weighs 6.37 grams. Calculate the number of moles o
    5·2 answers
  • 1. How many grams of chromium metal are plated out when a constant current of 8.00 A is passed through an aqueous solution conta
    15·1 answer
  • In the diagram below, particles of the substance are moving from the liquid phase to the gas phase at the same rate as they move
    11·2 answers
  • What do pH and conductivity have in common?
    6·2 answers
  • You are performing an experiment in your lab. To compare with other experiments you need your results to be in moles. During you
    12·2 answers
  • A certain gas expands to fill a 3 L container. Its mass is measured to be 0.6 kg. What is its density?
    7·1 answer
  • How will increasing the pressure on the system affect this equilibrium reaction? 2H2(g)+O2(g) -> 2H2O(g)
    6·1 answer
  • Calculate the heat of reaction, ΔH°rxn, for overall reaction for the production of methane, CH4.
    10·1 answer
  • 18) Why are the large oak trees so important for storks? Where are<br> they found?<br> 1
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!