Bihar Board 12th Chemistry Objective Important Questions Part 2 in English

Bihar Board 12th Chemistry Objective Important Questions Part 2 in English

BSEB 12th Chemistry Objective Important Questions Part 2 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

Question 47.
The catalyst used in the manufacture of sulphuric by lead chamber process is:
(a) Pt
(b) Ni
(c) NO
(d) N₂O₃
Answer:
(c) NO

Question 48.
The catalyst used in the manufacture of sulphuric acid by contact process:
(a) platinised asbestos
(b) Ni
(c) Fe
(d) NO
Answer:
(a) platinised asbestos

Question 49.
Bleaching action of SO₂ is due to :
(a) reduction
(b) oxidation
(c) its acidic nature
(d) hydrolysis
Answer:
(a) reduction

Question 50.
Cara’s acid is :
(a) H₂SO₅
(b) H₂SO₃
(c) H₃S₂O₅
(d) H₂S₂O₈
Answer:
(a) H₂SO₅

Question 51.
Marshall’s add is:
(a) H₂S₂O₅
(b) H₂S₂O₅
(c) H₂SO₅
(d) H₂SO₄
Answer:
(b) H₂S₂O₅

Question 52.
Sulphur dioxide is:
(a) only reducing agent
(b) only oxidising agent
(c) both oxidising and reducing agent
(d) none of the above
Answer:
(c) both oxidising and reducing agent

Question 53.
SO₂ is:
(a) acidic
(b) basic
(c) neutral
(d) ampholeric
Answer:
(a) acidic

Question 54.
Which compound acts as an oxidising as well as a reducing agent?
(a) SO₂
(b) SO₃
(c) CrO₃
(d) MnO₂
Answer:
(a) SO₂

Question 55.
The acid used in lead storage cell is :
(a) Phosphoric
(b) sulphuric acid
(c) hydrochloric
(d) nitric acid
Answer:
(b) sulphuric acid

Question 56.
Which one of the following is the strongest acid?
(a) HF
(b) HI
(c) HBr
(d) HCl
Answer:
(b) HI

Question 57.
Which one of the following is the strongest acid :
(a) HClO
(b) HClO₂
(c) HClO₃
(d) HClO₄
Answer:
(d) HClO₄

Question 58.
Which is the strongest oxidising agent?
(a) HCl
(b) HClO₂
(c) HClO₃
(d) HClO₄
Answer:
(a) HCl

Question 59.
Which one of the following has hydrogen bonding?
(a) HCl
(b) HBr
(c) HF
(d) HI
Answer:
(c) HF

Question 60.
The catalyst used in the deacon’s process for the manufacture of chlorine is:
(a) Cu
(b) An alloy of copper
(c) CuCl₂
(d) CuS
Answer:
(c) CuCl₂

Question 61.
Which one of the following acts as an antichlor :
(a) MnO₂
(b) Na₂S₂O₃
(c) K₂Cr₂O₇
(d) Na₂SO₄
Answer:
(b) Na₂S₂O₃

Question 62.
Slaked lime reacts with chlorine to form :
(a) Ca(OCl)Cl
(b) Ca(OCl)₂
(c) Ca(ClO₃)₂
(d) CaCl₂
Answer:
(a) Ca(OCl)Cl

Question 63.
The chemical name of bleaching powder is :
(a) Calcium hypochlorite
(b) Calcium chloro hypochlorite
(c) Calcium chlorate
(d) Calcium perchlorate
Answer:
(b) Calcium chloro hypochlorite

Question 64.
Which of the following elements does not belong to first transition series?
(a) Fe
(b) V
(c) Cu
(d) Ag
Answer:
(d) Ag

Question 65.
Transition elements are:
(a) s-block
(b) p-block
(c) d-block
(d) f-block
Answer:
(c) d-block

Question 66.
Dettol is:
(a) an antiseptic
(b) an antibiotic
(c) a tranquillizer
(d) an analgesic
Answer:
(a) an antiseptic

Question 67.
Paracetamol is :
(a) antihistamine
(b) antimalarial
(c) antipyretic
(d) tranquillizer
Answer:
(c) antipyretic

Question 68.
Which one of the following is a tranquillizer?
(a) barbituric acid
(b) aspirin
(c) chloroquine
(d) penicillin
Answer:
(a) barbituric acid

Question 69.
Which one of the following is an anti-histamine?
(a) Diphenhydramine
(b) aspirin
(c) chloroquine
(d) streptomycin
Answer:
(a) Diphenhydramine

Question 70.
The most common oxidation state shown by first row transition elements is:
(a) + 2
(b) + 3
(c) + 4
(d) All of these
Answer:
(a) + 2

Question 71.
Chloral is:
(a) CCl₃CHO
(b) CCl₃CH₃
(c) CCl₃COCH₃
(d) CCl₃CH₂OH
Answer:
(a) CCl₃CHO

Question 72.
Amongst the following the most reactive alkyl halide is :
(a) C₂H₅Br
(b) C₂H₅I
(c) C₂H₅Cl
(d) All are same
Answer:
(a) C₂H₅Br

Question 73.
Amongst the following which one is the most reactive?
(a) CH₃CH₂I
(b) C₂H₅Br
(c) (CH₃)₃Cl
(d) All are same
Answer:
(c) (CH₃)₃Cl

Question 74.
Ethyl iodide on treatment with moist silver oxide gives :
(a) acetic acid
(b) ethyl alcohol
(c) acetaldehyde
(d)none
Answer:
(b) ethyl alcohol

Question 75.
Amongst the following, the one having the highest boiling point is :
(a) C₂H₅Cl
(b) C₂H₅Br
(c) C₂H₅I
(d) CH₃Cl
Answer:
(c) C₂H₅I

Question 76.
Which one of the following will give ethyl alcohol when heated with moist silver oxide:
(a) CH₃I
(b) C₂H₅Br
(c) (CH₃)₂CHI
(d) CH₃-CH₂-CH₂I
Answer:
(b) C₂H₅Br

Question 77.
Amongst the following which one has the highest boiling point?
(a) ethyl alcohol
(b) n-propyl alcohol
(c) n-butyl alcohol
(d) methyl alcohol
Answer:
(c) n-butyl alcohol

Question 78.
Which one is the most acidic?
(a) CH₃OH
(b) C₂H₅OH
(c) CH₃·CH(OH)·CH₃
(d) CH₃·CH₂·CH₂OH
Answer:
(a) CH₃OH

Question 79.
Ethyl alcohol, when oxidised with acidic K₂Cr₂O₇ solution, gives:
(a) CH₃·COOH
(b) HCOOH
(c) CH₃·CO·CH₃
(d) None
Answer:
(a) CH₃·COOH

Question 80.
Which one of the following will give an aldehyde on oxidation with chromic anhydride in glacial acetic acid?
(a) CH₂COOH
(b) CH₃CH(OH)CH₃
(c) CH₃ CH₂OH
(d) None
Answer:
(c) CH₃ CH₂OH

Question 81.
Which one of the following will give a ketone on oxidation with acidic K₂Cr₂O₇ ?
(a) CH₃ CH₂OH
(b) CH₃CH (OH)CH₃
(c) CH₃OH
(d) None
Answer:
(b) CH₃CH (OH)CH₃

Question 82.
Which one of the following reduces Fehling’s solution?
(a) CH₃COOH
(b) CH₃COCH₃
(c) HCHO
(d) CH₃OH
Answer:
(c) HCHO

Question 83.
Which one of the following undergoes Cannizzaro reaction?
(a) HCHO
(b) CH₃ CHO
(c) CH₃COCH₃

Answer:
(a) HCHO

Question 84.
Dry distillation of calcium acetate will give :
(a) CH₃ COOH
(b) CH₃COCH₃
(c) CH₃ CHO
(d) CH₃ · CH₃
Answer:
(b) CH₃COCH₃

Question 85.
Which will turn blue litmus red?
(a) HCOOH
(b) CH₃CHO
(C) CH₃COCH₃
(d) None
Answer:
(a) HCOOH

Question 86.
When a mixture of calcium acetate and calcium formate is heated. it yields:
(a) acetone
(b) formic acid
(e) acetic acid
(d) acetaldehyde
Answer:
(d) acetaldehyde

Question 87.
Carboxylic acids do not give the characteristic properties of:
(a) >C = O group
(b) -COOH group
(c) Alkyl group
(d) none of these
Answer:
(a) >C = O group

Question 88.
Which one is a phenol?
(a) C₆H₅CH₂OH
(b) C₆H₅OH
(c) CH₃CH₂OH
(d) None
Answer:
(b) C₆H₅OH

Question 89.
Which is the strongest acid
(a) p-phenol
(b) m-phenol
(c) o-phenol
(d) phenol
Answer:
(a) p-phenol

Question 90.
Which of the following turns litmus red?
(a) CH₃CH₂OH
(b) C₆H₅CHO
(c) C₆H₅OH
(d) None
Answer:
(c) C₆H₅OH

Question 91.
Phenols do not react with :
(a) NaOH
(b) KOH
(c) NaHCO₃
(d) None
Answer:
(c) NaHCO₃

Question 92.
Amongst the following the most acidic oxide is:
(a) Sb₂O₅
(b) P₂O₅
(c) N₂O₅
(d) AS₂O₅
Answer:
(c) N₂O₅

Question 93.
The cause of variable valency-among transition dementias:
(a) They all exist in more than one oxidation state
(b) They all form complex compounds
(c) the valence electrons of them are found in two different subshells
(d) they all have paired electrons
Answer:
(c) the valence electrons of them are found in two different subshells

Question 94.
Which one is not a transition element?
(a) Co
(b) V
(c) Ge
(d) Rh
Answer:
(c) Ge

Question 95.
Froth floatation process is used :
(a) for calcination of ores
(b) for roasting of ores
(c) for concentration of ores
(d) for smelting of ores
Answer:
(c) for concentration of ores

Question 96.
Sulphide ores are concentrated by :
(a) gravity separation
(b) electromagnetic separation
(c) froth floatation process
(d) None of these
Answer:
(c) froth floatation process

Question 97.
Froth floatation process is used for the concentration of:
(a) sulphide ores
(b) carbonate ores
(c) oxide ores
(d) sulphate ores
Answer:
(a) sulphide ores

Question 98.
Which of the following ores is concentrated by froth floatation process:
(a) Bauxite
(b) cassiterite
(c) galena
(d) siderite
Answer:
(c) galena

Question 99.
When one Faraday of Electric current is passed. The Mass deposited is equal to :
(a) One gram equivalent
(b) One gram Mole
(c) Electro-chemical equivalent
(d) Half gram equivalent
Answer:
(a) One gram equivalent

Question 100.
Amongst the following the most acidic oxide is :
(a) N₂O₃
(b) N₂O₅
(c) N₂O₄
(d) All are same
Answer:
(b) N₂O₅

Question 101.
Thermally most stable oxide is :
(a ) P₂O₃
(b) As₂O₃
(c) Sb₂O₃
(d) N₂O₃
Answer:
(d) N₂O₃

Question 102.
Which is the most stable:
(a) N₂O₃
(b) N₂O₅
(c) N₂O₄
(d) All are same
Answer:
(a) N₂O₃

Question 103.
Which one is the most basic?
(a) NH₃
(b) AsH₃
(c) SbH₃
(d) PH₃
Answer:
(a) NH₃

Question 104.
Which one is the most stable?
(a) PH₃
(b) NH₃
(c) SbH₃
(d) AsH₃
Answer:
(b) NH₃

Question 105.
Which is stronger reducing agent?
(a) PH₃
(b) NH₃
(c) SbH₃
(d) AsH₃
Answer:
(c) SbH₃

Question 106.
Which of the folIowingeOmpounds is least acidic?
(a) H₂Se
(b) H₂O
(c) H₂S
(d) H₂Te
Answer:
(b) H₂O

Question 107.
Which of the following compounds is most stable?
(a) H₂O
(b) H₂Te
(c) H₂S
(d) H₂Se
Answer:
(a) H₂O

Question 108.
Which of the following is the strongest reducing agent?
(a) H₂O
(b) H₂Se
(c) H₂Te
(d) H₂S
Answer:
(c) H₂Te

Question 109.
Which of the following aqueous solution should have highest boiling point:
(a) 1.0 M NaOH
(b) 1.0 M Na₂SO₄
(c) 1.0 M NH₄NO₃
(d) 1.0 M KNO₃
Answer:
(b) 1.0 M Na₂SO₄

Question 110.
A solution has an osmotic pressure of 0.0821 atm at 300K. Its concentration would be:
(a) 0.66 M
(b) 0.32 M
(c) 0.066 M
(d) 0.0033 M
Answer:
(d) 0.0033 M

Question 111.
Azeotropic mixture of HCl and H₂O has :
(a) 48% HCl
(b) 22.2% HCl
(c) 36% HCl
(d) 20.2% HCl
Answer:
(d) 20.2% HCl

Question 112.
The rate at which a substance reacts depends upon its:
(a) Atomic mass
(b) Equivalent mass
(c) Molecular mass
(d) Active mass
Answer:
(d) Active mass

Question 113.
Which of the following is Tribasic :
(a) H₃PO₂
(b) H₃PO₃
(c) H₄P₂O₇
(d) H₃PO₄
Answer:
(d) H₃PO₄

Question 114.
Froth floatation process is based on :
(a) specific gravity of ore particles
(b) magnetic properties of the ore particles
(c) electrical properties of the ore particles
(d) wetting properties of the ore particles
Answer:
(d) wetting properties of the ore particles