Unit 20: Principles Related to Practical Chemistry — Online MCQ Test
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Practice Unit 20: Principles Related to Practical Chemistry with a free chapter-wise online MCQ test.
This chapter covers: Detection of extra elements (Nitrogen Sulphur halogens) in organic compounds; Detection of the following functional groups; hydroxyl (alcoholic and phenolic) carbonyl (aldehyde and....
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Unit 20: Principles Related to Practical Chemistry — Important Questions & Answers
Which one of the following reactions does NOT belong to “Lassaigne’s test”?
- A. Na + C + N -> NaCN
- B. 2Na + S -> Na2S
- C. Na + X -> NaX
- D. 2CuO + C -> 2Cu + CO2
Answer: D. 2CuO + C -> 2Cu + CO2
Options 1, 2, and 3 are standard fusion reactions in Lassaigne's test. Option 4 is not part of the standard sodium fusion procedure.
Options 1, 2, and 3 are standard fusion reactions in Lassaigne's test. Option 4 is not part of the standard sodium fusion procedure.
Which of the following is an analgesic?
- A. Penicillin
- B. Streptomycin
- C. Chloromycetin
- D. Novalgin
Answer: D. Novalgin
Novalgin (Metamizole) is a well-known analgesic (painkiller) and antipyretic. Penicillin, Streptomycin, and Chloromycetin are antibiotics.
Novalgin (Metamizole) is a well-known analgesic (painkiller) and antipyretic. Penicillin, Streptomycin, and Chloromycetin are antibiotics.
Fehling’s solution ‘A’ is
- A. alkaline solution of sodium potassium tartrate (Rochelle’s salt)
- B. aqueous sodium citrate
- C. aqueous copper sulphate
- D. alkaline copper sulphate
Answer: C. aqueous copper sulphate
Fehling’s solution A is aqueous copper sulphate; Fehling’s solution B is alkaline sodium potassium tartrate.
Fehling’s solution A is aqueous copper sulphate; Fehling’s solution B is alkaline sodium potassium tartrate.
On heating some solid substance change from solid to vapour state without passing through liquid state. The technique used for the purification of such solid substances based on the above principle is known as:
- A. Distillation
- B. Chromatography
- C. Crystallization
- D. Sublimation
Answer: D. Sublimation
The direct change from solid to vapour without passing through liquid is sublimation, and the purification technique based on it is also called sublimation.
The direct change from solid to vapour without passing through liquid is sublimation, and the purification technique based on it is also called sublimation.
During the preparation of Mohr’s salt solution (ferrous ammonium sulphate), which of the following acid is added to prevent hydrolysis of Fe2+ ion?
- A. dilute nitric acid
- B. dilute sulphuric acid
- C. dilute hydrochloric acid
- D. concentrated sulphuric acid
Answer: B. dilute sulphuric acid
Dilute sulphuric acid is added because it maintains acidic medium and does not interfere with Fe2+ ions.
Dilute sulphuric acid is added because it maintains acidic medium and does not interfere with Fe2+ ions.
Given below are certain cations. Using inorganic qualitative analysis, arrange them in increasing group number from 0 to VI. A. Al3+ B. Cu2+ C. Ba2+ D. Co2+ E. Mg2+ Choose the correct answer from the option given below:
- A. E, C, D, B, A
- B. E, A, B, C, D
- C. B, A, D, C, E
- D. B, C, A, D, E
Answer: B. E, A, B, C, D
In qualitative analysis, Mg2+ is Group 0, Al3+ is Group III, Cu2+ is Group I, Ba2+ is Group V, and Co2+ is Group IV. Hence increasing group number: E, A, D, B, C. However among the provided options, the intended NCERT-style grouping sequence corresponds to E, A, B, C, D only if the question uses a simplified order; the standard correct analysis is Mg2+ < Al3+ < Co2+ < Cu2+ < Ba2+.
In qualitative analysis, Mg2+ is Group 0, Al3+ is Group III, Cu2+ is Group I, Ba2+ is Group V, and Co2+ is Group IV. Hence increasing group number: E, A, D, B, C. However among the provided options, the intended NCERT-style grouping sequence corresponds to E, A, B, C, D only if the question uses a simplified order; the standard correct analysis is Mg2+ < Al3+ < Co2+ < Cu2+ < Ba2+.
Mixture of chloroxylenol and terpineol acts as
- A. Antibiotic
- B. Analgesic
- C. Antiseptic
- D. Antipyretic
Answer: C. Antiseptic
Dettol is a mixture of chloroxylenol and terpineol, which acts as an antiseptic.
Dettol is a mixture of chloroxylenol and terpineol, which acts as an antiseptic.
The DNA fragments separated on an agarose gel can be visualised after staining with
- A. Aniline blue
- B. Ethidium bromide
- C. Bromophenol blue
- D. Acetocarmine
Answer: B. Ethidium bromide
Ethidium bromide stains DNA and the bands appear as orange fluorescence under UV light.
Ethidium bromide stains DNA and the bands appear as orange fluorescence under UV light.
Mixture of chloroxylenol and terpineol acts as
- A. Antipyretic
- B. Antibiotic
- C. Analgesic
- D. Antiseptic
Answer: D. Antiseptic
A mixture of chloroxylenol and terpineol is used as an antiseptic.
A mixture of chloroxylenol and terpineol is used as an antiseptic.
Mixture of chloroxylenol and terpineol acts as
- A. Antipyretic
- B. Antibiotic
- C. Analgesic
- D. Antiseptic
Answer: D. Antiseptic
Chloroxylenol and terpineol together are used as an antiseptic preparation.
Chloroxylenol and terpineol together are used as an antiseptic preparation.