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erastovalidia [21]

2 years ago

12

In this experiment, 0.170 g of caffeine is dissolved in 10.0 ml of water. the caffeine is extracted from the aqueous solution th

ree times with 5.0-ml portions of methylene chloride. calculate the total amount of caffeine that can be extracted into the three portions of methylene chloride (see technique 12, section 12.2). caffeine has a distribution coefficient of 4.6 between methylene chloride and water.

1 answer:

zmey [24]2 years ago

6 0

solution:

Weight of caffeine is W = 0.170 gm.

Volume of water is V= 10 ml

Volume of methylene chloride which extracted caffeine is v= 5ml

No of portions n=3

Distribution co-efficient= 4.6

Total amount of caffeine that can be unextracted is given by

$w_{n}=w\times[\frac{k_{Dx}v}{k_{Dx}v+v}]^n\\w_{3}=0.170[\frac{4.6\times10}{(4.6\times10+5)}]^3\\=0.170[\frac{46}{46+5}]^3\\=0.170[\frac{46}{51}]^3\\=0.170[\frac{97336}{132651}]\\=0.170\times0.734=0.125gms$

amount of caffeine un extracted is 0.125gms

amount of caffeine extracted=0.170-0.125

=0.045 gms

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1 year ago

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2 years ago

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For calculating the mass of hydrogen:

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For calculating the mass of oxygen:

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To formulate the empirical formula, we need to follow some steps:

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Moles of Hydrogen = $\frac{\text{Given mass of Hydrogen}}{\text{Molar mass of Hydrogen}}=\frac{0.121g}{1g/mole}=0.121moles$

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Step 3: Taking the mole ratio as their subscripts.

The ratio of C : H : O = 2 : 3 : 1

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Now we have to calculate the molecular formula of the compound.

Formula used :

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Therefore, the molecular of the compound is, $C_2H_3O$

6 0

1 year ago