12th Grade > Chemistry
REACTION MECHANISM MCQs
Total Questions : 15
| Page 1 of 2 pages
Answer: Option C. -> Ph−O−Et
:
C
Watch the video that follows!
:
C
Watch the video that follows!
Answer: Option B. -> The second reaction occurs faster than the first
:
B
Polar aprotic solvents such as DMSO increase the rate of the SN2 reaction.
:
B
Polar aprotic solvents such as DMSO increase the rate of the SN2 reaction.
Answer: Option D. -> Due to +E effect of Cl
:
D
Cl is involved in resonance as well as inductive effect and not in electrometric effect as it is more electronegative.
:
D
Cl is involved in resonance as well as inductive effect and not in electrometric effect as it is more electronegative.
Answer: Option C. -> Cl
:
C
Acid halides react fastest among acid derivates.
:
C
Acid halides react fastest among acid derivates.
Answer: Option C. -> Cl
:
C
In protic solvent E2 proceeds over SN2.
:
C
In protic solvent E2 proceeds over SN2.
Question 6. A solution containing 0.2563 g of naphthalene (molecular mass = 128) in 50 g of carbon tetrachloride yields a boiling point elevation of 0.201∘C while a solution of 0.6216 g of an unknown solute in the same mass of the solvent gives a boiling point elevation of 0.647∘C. Find the molecular mass of unknown solute.
Answer: Option A. -> 96.44
:
A
We know that
Kb=ΔTb×W1×Mw21000×W2
First let’s calculate value of KbforCCl4.
For CCl4;
Kb=0.201×50×1281000×0.2563=5.019kkgmol−1
Now, for calculating mass of unknown solute, we can use the same value of Kb.
Mw2=1000×Kb×W2ΔTb×W1
1000×5.019×0.62160.647×50
=96.44
:
A
We know that
Kb=ΔTb×W1×Mw21000×W2
First let’s calculate value of KbforCCl4.
For CCl4;
Kb=0.201×50×1281000×0.2563=5.019kkgmol−1
Now, for calculating mass of unknown solute, we can use the same value of Kb.
Mw2=1000×Kb×W2ΔTb×W1
1000×5.019×0.62160.647×50
=96.44
Answer: Option C. -> II > III > I
:
C
The reactivity decreases in the order
Allylic > Secondary > primary.
:
C
The reactivity decreases in the order
Allylic > Secondary > primary.