Bihar Board 12th Chemistry Objective Important Questions Part 4 in English

BSEB Bihar Board 12th Chemistry Important Questions Objective Type Part 4 are the best resource for students which helps in revision.

Bihar Board 12th Chemistry Objective Important Questions Part 4 in English

Question 1.
The general electronic configuration of inner transition elements is :
(a) (n-2)f^1-7(n-1)d¹ns¹
(b) (n-2)f^1-14(n-1)d^{0 or 1} ns¹
(c) (n-2)f^1-14(n-1)a^{0 or 1} ns²
(d) none
Answer:
(c) (n-2)f^1-14(n-1)a^{0 or 1} ns²

Question 2.
In the first transition series the highest oxidation state is exhibited by:
(a) Mn
(b) Ni
(c) Fe
(d) Cr
Answer:
(a) Mn

Question 3.
Brass is an alloy containing
(a) Cu and Zn
(b) Cu and Sn
(c) Zn and S
(d) Cu, Zn and Sn
Answer:
(a) Cu and Zn

Question 4.
Iron ores are concentrated by:
(a) gravity separation process
(b) froth floatation method
(c) amalgamation
(d) handpicking
Answer:
(a) gravity separation process

Question 5.
Purest form of iron is :
(a) pig iron
(b) cast iron
(c) wrought iron
(d) steel
Answer:
(c) wrought iron

Question 6.
Green vitriol is :
(a) ZnSO₄. 7H₂O
(b) FeSO₄. 7H₂O
(c) CuSO₄. 5H₂O
(d) Na₂SO₄. 10H₂O
Answer:
(b) FeSO₄. 7H₂O

Question 7.
Vitamin-B12 contains:
(a) CO³⁺
(b) Cu²⁺
(c) Zn²⁺
(d) Fe²⁺
Answer:
(a) CO³⁺

Question 8.
Primary amine on treatment with NaNO₂ and HCl yields :
(a) nitro compound
(b) ammonia
(c) secondary alcohol
(d) primary alcohol
Answer:
(d) primary alcohol

Question 9.
Ethyl alcohol is obtained when ethyl chloride is boiled with:
(a) alcoholic
(b) aqueous KOH
(c) water
(d) H₂O₂
Answer:
(b) aqueous KOH

Question 10.
Which of the following does not give iodoform?
(a) CH₃OH
(b) C₂H₅OH
(c) CH₃CHO
(d) CH₃COCH₃
Answer:
(a) CH₃OH

Question 11.
An alkyl halide reacts with metallic sodium in dry ether. The reaction is known as :
(a) Frankland’s reaction
(b) Sandmeyer’s reaction
(c) Wurtz reaction
(d) Wurtz-Fittig reaction
Answer:
(c) Wurtz reaction

Question 12.
Which gives iodoform test?
(a) Propanone
(b) butanone
(c) 2-pentanone
(d) all of these
Answer:
(d) all of these

Question 13.
Which is detected by carbyl amine test?
(a) NH₂ . CO. NH₂
(b) CH₃CONH₂
(c) C₂H₅NH₂
(d) all of these
Answer:
(c) C₂H₅NH₂

Question 14.
Which of the following will give a yellow precipitate with I₂ and NaOH?
(a) ICH₂COOCH₂CH₃
(b) CH₃COOCOCH₃
(c) CH₃CONH₂
(d) CH₃CH (OH)CH₂CH₃
Answer:
(d) CH₃CH (OH)CH₂CH₃

Question 15.
Which one is a primary alcoholic group?
(a) -CH₂OH
(b) > CH . OH
(c) > C – OH

Answer:
(a) -CH₂OH

Question 16.
Monohydric alcohols have the general formula :
(a) CnH_2nO
(b) CnH_2n+1O
(c) CnH_2n+2O
(d) CnH_2n+4
Answer:
(c) CnH_2n+2O

Question 17.
Which one of the following alcohols reacts most readily with-lucas reagent?
(a) CH₃. CH₂ CH₂OH
(b) (CH₃)₂CHOH
(c) (CH₃)₃COH
(d) CH₃.CH₂OH
Answer:
(c) (CH₃)₃COH

Question 18.
Butan-2-ol is a :
(a) primary alcohol
(b) secondary alcohol
(c) tertiary alcohol
(d) dihydric alcohol
Answer:
(b) secondary alcohol

Question 19.
Ethyl alcohol oh oxidation with dil. acidic K₂Cr₂O₇ solution finally gives:
(a) formic acid
(b) formaldehyde
(c) acetic acid
(d) acetaldehyde
Answer:
(c) acetic acid

Question 20.
Which of the following enzymes converts glucose into ethyl alochol:
(a) diastase
(b) invertase
(c) maltase
(d) zymase
Answer:
(d) zymase

Question 21.
Which of the following chemicals Is used for the denaturation of ethyl alcohol:
(a ) CH₃OCH₃
(b) Pyridine
(c) anhydrous CaCl₂
(d) naphtha
Answer:
(b) Pyridine

Question 22.
Williamson’s synthesis is used to prepare :
(a) ethers
(b) acetone
(c) PVC
(d) backelite
Answer:
(a) ethers

Question 23.
Dry distillation of calcium acetate will give :
(a) CH₃COOH
(b) CH₃COCH₃
(c) HCHO
(d) CH₃CHO
Answer:
(b) CH₃COCH₃

Question 24.
Dry heating of a mixture of calcium acetate and calcium formate yields:
(a) acetone
(b) acetaldehyde
(c) formic acid
(d) formaldehyde
Answer:
(b) acetaldehyde

Question 25.
Which of following classes of compounds gives Tollins reagent test?
(a) alcohols
(b) aldehydes
(c) ketones
(d) ethers
Answer:
(b) aldehydes

Question 26.
Aldehydes and ketones may be distinguished by :
(a) Lucas reagent
(b) Tollen’s reagent
(c) Baeyer’s reagent
(d) Fenton’s reagent
Answer:
(b) Tollen’s reagent

Question 27.
An aldehyde on oxidation gives :
(a) an acid
(b) an alcohol
(c) an ether
(d) an ester
Answer:
(a) an acid

Question 28.
Vitamin C is:
(a) ascorbic acid
(b) nicotinic acid
(c) citric acid
(d) tartaric acid
Answer:
(a) ascorbic acid

Question 29.
Enzymes are:
(a) Proteins
(b) Lipids
(c) Carbohydrates
(d) None of these
Answer:
(a) Proteins

Question 30.
Rickets is caused due to deficiency of:
(a) Vitamin A
(b) Vitamin B
(c) Vitamin C
(d) Vitamin D
Answer:
(d) Vitamin D

Question 31.
Which of the following is an antibiotic:
(a) terramycin
(b) aspirin
(c) paracetamol
(d) chloroquine
Answer:
(a) terramycin

Question 32.
Which of the following is used as an antipyretic?
(a) paracetamol
(b) chloroquine
(c) terramycin
(d) chloramphenicol
Answer:
(a) paracetamol

Question 33.
Reserpine is
(a) tranquillizer
(b) antibiotic
(c) Vitamin
(d) harmone
Answer:
(a) tranquillizer

Question 34.
Terylene is:
(a) polyamide
(b) polyethylene
(c) polyester
(d) polyvinyl chloride
Answer:
(c) polyester

Question 35.
Orion is a ploymer of:
(a) styrene
(b) vinyl chloride
(c) tetrafluoroethene
(d) acrylonitrile
Answer:
(d) acrylonitrile

Question 36.
The monomer of teflon is :
(a) monofluoro ethene
(b) difluoro ethene
(c) trifiuoroethene
(d) tetrafluoro ethene
Answer:
(d) tetrafluoro ethene

Question 37.
Which one of the following is a thermosetting plastic?
(a) PVC
(b) PVA
(c) Bakelite
(d) Perspex
Answer:
(c) Bakelite

Question 38.
Chloroquine is:
(a) an analgesic
(b) antibiotic
(c) an antimalarial
(d) an antipyretic
Answer:
(c) an antimalarial

Question 39.
Morphine is:
(a) antiseptic
(b) analgesic
(c) antibiotic
(d) anaesthetic
Answer:
(b) analgesic

Question 40.
Phenol is used as:
(a) an antiseptic
(b) an insecticide
(c) a disinfestant
(d) styptic
Answer:
(a) an antiseptic

Question 41.
Tranquillizers are used for the treatment of:
(a) Cancer
(b) AIDS
(c) Mental diseases
(d) Blood infection
Answer:
(c) Mental diseases

Question 42.
Lucas reagent is:
(a) anhydrous ZnCl₂ and conc. HCl
(b) MnO₂
(c) H₂SO₄ and HCl
(d) Na + H₂O
Answer:
(a) anhydrous ZnCl₂ and conc. HCl

Question 43.
Primary, secondary and tertiary alcohols are distinguished by :
(a) Oxidation method
(b) Lucas test
(c) Victor Meyer’s method
(d) all of these
Answer:
(d) all of these

Question 44.
CH₃OH and C₂H₅OH may be distinguished chemically :
(a) by the action of HCl
(b) By iodoform test
(c) by the action of NH₃
(d) solubility in water
Answer:
(b) By iodoform test

Question 45.
The oxidation state of Ni in Ni(CO)₄ is :
(a) +1
(b) +2
(c) +4
(d) 0
Answer:
(d) 0

Question 46.
Iodoform is formed on warming iodine and sodium hydroxide with :
(a) CH₃OH
(b) HCOOH
(c) C₂H₅OH
(d) C₂H₆
Answer:
(c) C₂H₅OH