Laboratory Techniques in Organic Chemistry
4th Edition
ISBN: 9781464134227
Author: Jerry R. Mohrig, David Alberg, Gretchen Hofmeister, Paul F. Schatz, Christina Noring Hammond
Publisher: W. H. Freeman
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Question
Chapter 15, Problem 5Q
Interpretation Introduction
Interpretation:
The reason for the use of gravity filtration rather than vacuum filtration for hot recrystallization solution should be determined.
Concept introduction:
Recrystallization is a process in which an impure crystalline solid dissolved in hot solvent precipitates back when the solvent is cooled and that leads to formation of pure solid crystals. For successful recrystallization, maximum solubility of solute in hot solvent is essential and in cold solvent the solubility should be minimum for the maximum yield of crystals.
If solute will have good solubility in cold solvent, there will be loss of compound on recrystallization. To minimize this loss, the choice of the solvent for recrystallization is important.
When a solute is dissolved in an appropriate solvent at an appropriate rate, temperature and concentration then it results in the formation of perfect crystal.
Filtration is a purification technique used for purification of an organic liquid to make them free from solid impurities. The two kinds of filtration techniques used in
- Gravity filtration.
- Vacuum filtration.
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Students have asked these similar questions
For the reaction 2 N2O5(g) → 4 NO2(g) + O2(g), the following mechanism has been proposed:
N2O5 →> NO₂+ NO3_(K1)
NO2 + NO3 → N2O5 (k-1)
NO2 + NO3 →
→
NO2 + O2 + NO (K2)
NO + N2O5-
NO2 + NO2 + NO2 (K3)
d[N₂O5] __2k‚k₂[N2O5]
Indicate whether the following rate expression is acceptable:
dt
k₁₁+ k₂
Consider the following decomposition reaction of N2O5(g):
For the reaction 2 N2O5(g) → 4 NO2(g) + O2(g), the following mechanism has been proposed:
N2O5 → NO2 + NO3 (K1)
NO2 + NO3 → N2O5 (k-1)
NO2 + NO3 → NO2 + O2 + NO (K2)
NO + N2O5 → NO2 + NO2 + NO2 (K3)
Indicate whether the following rate expression is acceptable:
d[N2O5]
= -k₁[N₂O₂] + K¸₁[NO₂][NO3] - K¸[NO₂]³
dt
In a reaction of A + B to give C, another compound other than A, B or C may appear in the kinetic equation.
Chapter 15 Solutions
Laboratory Techniques in Organic Chemistry
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Similar questions
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