Answer:
75 mg
Explanation:
We can write the extraction formula as
x = m/[1 + (1/K)(Vaq/Vo)], where
x = mass extracted
m = total mass of solute
K = distribution coefficient
Vo = volume of organic layer
Vaq = volume of aqueous layer
Data:
m = 75 mg
K = 1.8
Vo = 0.90 mL
Vaq = 1.00 mL
Calculations:
For each extraction,
1 + (1/K)(Vaq/Vo) = 1 + (1/1.8)(1.00/0.90) = 1 + 0.62 = 1.62
x = m/1.62 = 0.618m
So, 61.8 % of the solute is extracted in each step.
In other words, 38.2 % of the solute remains.
Let r = the amount remaining after n extractions. Then
r = m(0.382)^n.
If n = 7,
r = 75(0.382)^7 = 75 × 0.001 18 = 0.088 mg
m = 75 - 0.088 = 75 mg
After seven extractions, 75 mg (99.999 %) of the solute will be extracted.
Answer:
1.64g
Explanation:
The reaction scheme is given as;
2-bromocyclohexanol --> 1,2-epoxycyclohexane + HBr
From the reaction above,
1 mol of 2-bromocyclohexanol produces 1 mol of 1,2-epoxycyclohexane
3.0 grams of trans-2-bromocyclohexanol.
Molar mass = 179.05 g/mol
Number of moles = mass / molar mass = 3 / 179.05 = 0.016755 mol
This means 0.016755 mol of 1,2-epoxycyclohexane would be produced.
Molar mass = 98.143 g/mol
Theoretical yield = Number of moles * Molar mass
Theoretical yield = 0.016755 * 98.143 ≈ 1.64g
B. the shape of a molecule determines its properties and interactions
Explanation:
it is used to describe those action of adrenal corticosteroids that produce sodium
