Organic Chemistry Interview Questions and Answers for freshers on “Quantitative and Qualitative Analysis”.
1. Identify the one which does not come under the chemical methods of quantitative analysis?
a) Gravimetric
b) Titrimetric
c) Volumetric
d) Magnetic suceptibility
Answer: d
Clarification: Magnetic suceptibility comes under physical methods of qunatitative analysis and hence the answer.
2. Quantitative analysis is one which is used for separating out the specific constituents from a mixture.
a) True
b) False
Answer: b
Clarification: Quantitative analysis is used to measure the quantity, (i.e the amount) present and the above mentioned statement defines qualitative analysis.
3. Select the incorrect statement regarding analytical balance.
a) It is the fundamental kit in quantitative analysis
b) It measures samples very accurately
c) It could measure the difference in mass upto 0.1 mg
d) It is not a sensitive instrument
Answer: d
Clarification: It is a very sensitive instrument as it could accurately measure the weight of a particular compound of upto 0.1 mg.
4. Which among the following is not a physical method?
a) X-ray fluorescence spectroscopy
b) Atomic emission spectroscopy
c) Inert gas fusion
d) Trace element analysis
Answer: c
Clarification: Inert gas fusion is an example of chemical methods of quantitative analysis, as it involves chemical reaction such as oxidation.
5. Select the inappropriate statement regarding quantitative analysis.
a) It helps in determining the outcome of the product
b) It helps in determining the impurities in the sample
c) It fails to indicate the presence of lead in some compound
d) It could identify the amounts of dosage present in the drug
Answer: c
Clarification: It can identify the presence of lead and could also account for its concentration in case of paints and toys.
6. Identify the test which is not a part of qualitative analysis?
a) Litmus test
b) Kastle-Meyer test
c) Iodine test
d) Flame test
Answer: a
Clarification: Kastle-meyer test is done for identification of blood, Iodine test is done for identification of starch and Flame test is done to identify Barium.
7. Covalent molecules can be identified using quantitative methods.
a) False
b) True
Answer: a
Clarification: The qualitative analysis is used to identify covalent molecules by distinguishing them using physical properties such as melting point, etc.
8. Identify the reagent which is not commonly used in qualitative analysis?
a) 6M NaOH
b) 6M HCl
c) 6M HNO3
d) 6M NH4
Answer: d
Clarification: 6M NH3 is the reagent commonly used in qualitative analysis because it is used in almost every group procedures.
9. Select the correct statement about the reagent 6M HNO3.
a) It forms hydroxo complexes
b) It destroys hydroxo and ammonia complexes
c) It forms NH3 complexes
d) It decreases the H+ ion concentration
Answer: b
Clarification: It is a good oxidizing agent, dissolves in insoluble hydroxides and it destroys hydroxo and ammonia complexes.
10. Identify the incorrect statement regarding the reagent 6M NH3.
a) It increases hydroxide and NH3 concentration
b) It decreases H+ concentration
c) It is capable of precipitating insoluble hydroxides
d) It is capable of forming hydro complexes
Answer: d
Clarification: It forms only NH3 complexes and does not form hydro complexes.
Organic Chemistry for Interviews,