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3 years ago

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Chemistry

2 answers:

Stells [14]3 years ago

7 0

Its gonna be to learn about history on earth

Nikitich [7]3 years ago

5 0

The first option is the correct answer. Fossils belong to dinosaurs that lived in B.C/A.D, which scientists study to learn about Earth's prehistoric times.

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Th e molar absorption coeffi cient of a substance dissolved in water is known to be 855 dm3 mol−1 cm−1 at 270 nm. To determine t

Olegator [25]

Answer : The percentage reduction in intensity is 79.80 %

Explanation :

Using Beer-Lambert's law :

$A=\epsilon \times C\times l$

$A=\log \frac{I_o}{I}$

$\log \frac{I_o}{I}=\epsilon \times C\times l$

where,

A = absorbance of solution

C = concentration of solution = $3.25mmol.dm^{3-}=3.25\times 10^{-3}mol.dm^{-3}$

l = path length = 2.5 mm = 0.25 cm

$I_o$ = incident light

$I$ = transmitted light

$\epsilon$ = molar absorptivity coefficient = $855dm^3mol^{-1}cm^{-1}$

Now put all the given values in the above formula, we get:

$\log \frac{I_o}{I}=(855dm^3mol^{-1}cm^{-1})\times (3.25\times 10^{-3}mol.dm^{-3})\times (0.25cm)$

$\log \frac{I_o}{I}=0.6947$

$\frac{I_o}{I}=10^{0.6947}=4.951$

If we consider $I_o$ = 100

then, $I=\frac{100}{4.951}=20.198$

Here 'I' intensity of transmitted light = 20.198

Thus, the intensity of absorbed light $I_A$ = 100 - 20.198 = 79.80

Now we have to calculate the percentage reduction in intensity.

$\% \text{reduction in intensity}=\frac{I_A}{I_o}\times 100$

$\% \text{reduction in intensity}=\frac{79.80}{100}\times 100=79.80\%$

Therefore, the percentage reduction in intensity is 79.80 %

3 0

3 years ago

Give two examples of halohydrin formation

BigorU [14]

Answer:

Bromohydrin and chlorohydrin are examples of halohydrins (where X = Br or Cl).

8 0

1 year ago

1)Define potential Energy.

Margarita [4]

1. Potential Energy is stored energy a object has when it's not moving.

2. Potential Energy is it's highest on the first stage because as you see the roller coaster is bout to go down the tract which is going to higher the kinetic energy and lower the potential energy.

3. Kinetic Energy is the amount of energy a object has when it's in motion or moving.

4. Kinetic Energy is it's highest in the third stage after it's gone down the tract and potential energy fully decreased and it's at zero.

Remember that potential energy is stored energy so when a object is not moving in this case the roller coaster isn't moving on the first stage when its bout to go down the roller coaster. Kinetic energy is the amount of energy a object has when it's in motion so in this case the third stage would have the highest example of Kinetic energy because it's fully in motion and has no potential energy.

4 0

3 years ago

How would you separate a mixture of 4-tert-butylphenol and 2- chlorobenzoic acid? Explain the detailed steps including the choic

Sergeu [11.5K]

The a mixture of 4-tert-butylphenol and 2- chlorobenzoic acid is separate by the by using bicarbonate solvent.

When solution of bicarbonate is added in mixture of 4-tert-butylphenol and 2- chlorobenzoic acid then 2- chlorobenzoic acid form a carboxylate ion whereas 4-tert-butylphenol is underacted and filtered out.

Since, only 2- chlorobenzoic acid which is acid is convert into its conjugate base by solution of bicarbonate in mixture of 4-tert-butylphenol and 2- chlorobenzoic acid .

However, phenol is less acidic than carboxylic acid. Both phenol and carboxylic acid is soluble in organic solvent . At that point as the phenol isolates as an oil, one needs to cool the blend in an ice shower to encourage crystallization

to learn more about 4-tert-butylphenol

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7 0

1 year ago

Answer my question please!

BaLLatris [955]

Answer:

D) 6

Explanation:

The complete balancd equation:

6Li + 1N2 = 2 Li3N

6 0

2 years ago