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3 years ago

Someone pls help me with this before i k word myself

Chemistry

1 answer:

katrin2010 [14]3 years ago

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D‑Glucose and L‑glucose are

tensa zangetsu [6.8K]

Answer:

<h3>A. Epimers </h3>

Explanation:

3 0

3 years ago

Read 2 more answers

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

4 years ago

You have to prepare some 2 M solutions, with 10 g of solute in each. What volume of solution will you prepare, for each solute b

alexdok [17]

Answer:

0.045 L or 45 mL

Explanation:

Moles = Mass/M.Mass

Moles = 10 g / 109.94 g/mol

Moles = 0.09 moles

Also,

Molarity = Moles / Vol in L

Or,

Vol in L = Moles / Molarity

Vol in L = 0.09 mol / 2 mol/L

Vol in L = 0.045 L

8 0

2 years ago

What are the four bases found in DNA molecule???? Please send helppppp

alukav5142 [94]

Answer:

DNA consists of molecules called nucleotides. Each nucleotide comprises a group of phosphates, a group of sugars and a base of nitrogen. The four forms of nitrogen bases are adenine (A), thymine (T), guanine (G) and cytosine (C). The sequence of these bases defines the DNA instructions or genetic code.

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3 years ago

The law of reflection states that if the angle of incidence is 43 degrees, the angle of reflection is ___ degrees.

Vesna [10]

43 degrees

angle of reflection is equal to the angle of incidence

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3 years ago