Explore topic-wise InterviewSolutions in Current Affairs.

This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.

1.

Dinitrogen pentoxide decomposes to NO_(2) and O_(2) following first order kinetics N_(2)O_(5)(g) rarr 2NO_(2)+O_(2)(g) 0.2 mole of N_(2)O_(5) was taken in 2L vessel and heated at 200K. The concentrated of N_(2)O_(5) is measured at different intervals . Following graphs A and B were obtained from the data. Slope of straight line in graph (B ) is - 6670 . Calculate the activation energy for the reaction

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12.77kJ
127.71049kJ
127.70149J
1.27kJ

Answer :B
2.

Dinitrogen pentoxide decomposes to NO_(2) and O_(2) following first order kinetics N_(2)O_(5)(g) rarr 2NO_(2)+O_(2)(g) 0.2 mole of N_(2)O_(5) was taken in 2L vessel and heated at 200K. The concentrated of N_(2)O_(5) is measured at different intervals . Following graphs A and B were obtained from the data. Slope of straight line in graph 'A' is -1 .2 xx 10^(2)sec^(-1) . What is half life of the reaction ?

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`2.5 XX 10^(-2) s `
`2.5 xx 10^(-3)`
`12.5 xx 10^(-4)`
`2.5 xx 10^(-3) m`

ANSWER :B
3.

Dinitrogen pentoxide dissolve in water to give :

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`HNO_(2)`
`H_(2)N_(2)O_(2)`
`NO_(2)`
`HNO_(3)`.

SOLUTION :`N_(2)O_(5)+H_(2)Orarr 2HNO_(3)`
4.

Dinitrogen (N_(2)) and dioxygen (O_(2)) are the main constituents of air but they do not react with each other to form oxides of nitrogen because

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the REACTION requires initiation by a catalyst
oxides of nitrogen are unstable
the REACTIONIS endothermic and requires very high temperature
the stoichiometry of `N_(2)` and `O_(2)` in air is not ideal for the reaction to take place

Solution :Copper metals when exposed to air turns green in colour due to corrosion. When copper vessel is exposed to air in rainy season , the metals reacts with gases and moisture and atmospheric gases to form a mixture of copper carbonate and copper hydroxide . This gives a green colour to the surface of copper METAL.
The reaction is as follows :
`2Cu + H_(2)O + CO_(2) + O_(2) to Cu (OH)_(2) + CuCO_(3)`
5.

Dinitrogen pentoxide decomposes as follows 2N_2O_5 to 4NO_2+O_2, The rate can be given in three ways (-d[N_2O_5])/(dt)=k_1[N_2O_5],(d[NO_2])/(dt)=k_2[N_2O_5],(d[O_2])/(dt)=k_3[N_2O_5] The relation between the rate constants k_1,k_2 and k_3 is

Answer»

`k_2=2k_1 and k_3=1//2k_1`
`k_1=2k_2 and k_3=2k_1`
`k_1=k_2=k_3`
`k_1=2k_2=3k_3`

ANSWER :A
6.

Dinitrogen gas is evolved when sodium nitrite is heated :

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alone
with AMMONIUM chloride
with ammonium HYDROXIDE
with potassium NITRATE

Solution :`NaNO+NH_(4)CL to NaCl+N_(2)+2H_(2)O`
7.

Dinitrogen can be purified from the impurities of NO and NH_(3) by passing through :

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concentrated `HCl`
alkaline SOLUTION of phrogallol.
an acidified SOLUTIN of potassium DICHROMATE.
an aqueous solution of `KOH`.

Solution :`K_(2)Cr_(2)O_(7)+H_(2)SO_(4)+Cr(SO_(4))_(3)+H_(2)O+[O],NO+[O]+H_(2)O toHNO_(3)(l)2NH_(3)+H_(2)SO_(4) to (NH_(4))_(2)SO_(4)`
8.

Dinitrogen cannot be librated by :

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decompostion of ammonium dichromate.
reaction of ammonia with heated CUPRIC
reaction of ammonia with bleaching powder.
heating ammonium CARBONATE.

Solution :Heating of ammonium carbonate does not give `N_(2)` but INSTEAD it LIBERATES `NH_(3)`.
`(NH_(4))_(2)CO_(3)overset(DELTA)to2NH_(3)+CO_(2)+H_(2)O`
9.

Dinitrogen and dioxygen are mainconstituentsof air but thesedo not react witheachotherto formoxides of nitrogenbecause "____"

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thereactionis endothermicand requiresvery HIGH TEMPERATURE.
the reactioncan beinitiated only in presence of a catalyst.
oxidesof nitrogenare UNSTABLE .
`N_(2) ` and `O_(2)` UNREACTIVE .

Answer :A
10.

Dinitrogen and dioxygen are main constituents of air but these do not react with each other to form oxides of nitrogen because ____ _

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the reaction can be INITIATED only in presence of a catalyst.
oxides of NITROGEN are unstable
`N_(2) and O_(2)` are unreactive
`N_(2) and O_(2)` are reactive

Answer :A
11.

Dinitrogen and dihydrogen react with each other to produce ammonia according to the chemical equation : ""N_(2)(g)+3H_(2)(g) rarr 2NH_(3)(g) (i) Calculate the mass of ammonia produced if 2.00xx10^(3) g dinitrogen reactw with 1.00xx10^(3)g dihydrogen (ii) Will any of the two reactants remain unreacted? (iii) If yes, which one and what would be its mass?

Answer»

Solution :(i) `"1 mole of N"_(2)," i.e., 28 g react with 3 moles of H"_(2)," i.e., 6 g of H"_(2)`
`therefore " 2000g of N"_(2)" will react with "H_(2)=(6)/(28)xx200g=428.6g." Thus, "N_(2)" is the limiting reagent while H"_(2) " isthe excess reagent."`
2 moles of `N_(2)`, i.e., 28 g of `N_(2)` produce `NH_(3)` = 2 moles = 34 g
`therefore "2000 g of N"_(2)" will produce NH"_(3)=(34)/(28)xx2000g=22428.57g`
(ii) `H_(2)` will remain unreacted.
(iii) MASS LEFT unreacted `=1000g-428.6g=571.4g`
12.

Dinitration of 3-methyl-phenol gives the following major product.

Answer»




ANSWER :C
13.

Dimethyl glyoxime is added to alcoholic solution of NiCl_(2). When ammonium hydroxide is slowly added to it, a rosy red precipitate of a complex appears (i) Give the structure of the complex showing hydrogen bonds. (ii) Give oxidation state and hybridisation of central metal ion. (iii) Identify whether it is paramagnetic or diamagnetic.

Answer»

SOLUTION :
(ii) Oxidation state of Ni in the complex = + 2
Hybridisation = `dsp^(2)` (because it is a planar MOLECULE)
(III) It is diamagnetic (because there is no unpaired electron present).
14.

Dimethylglyoxime is used for estimation of

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NICKEL
COBALT
MANGANESE
Aluminium.

Answer :A
15.

Dimethyl terephthalateis a ester of

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Phthalicacid
terephthalic ACID
OXALIC acid
carproic acid

ANSWER :B
16.

Dimethyl terephthalate and ethylene glycol react to form

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nylon-66
nylon-6
neoprene
dacron

Solution :We KNOW that , dacron (terlene ) is obtained by dimethyl terphthalate with ethylene glycol. Dacron is SLIGHTLY hygroscopic and has ELASTIC recovery . It is non -inglammable and melts at 533 K.
17.

Dimethyl glyoxime form asquare planar complex with Ni^(+2) . This complex contain how many number of unpaired electrons ?

Answer»


SOLUTION :`[Ni(DMG)_2]` is SQUARE PLANAR with `dsp^2` HYBRIDISATION
18.

Dimethyl ether is associated with which one of the isomer?

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Ethanol
Methanol
Formic acid
Methyl formate

Answer :A
19.

Dimethyl ether can be decomposed by heating with

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`H_2O`
NAOH
`KMnO_4`
HI

Answer :D
20.

Dimethyl ether into formic acid

Answer»

Solution :Dimethyl ether into formic acid :
`CH_(3)-O-CH_(3)+underset("DIL.")(H_(2)SO_(4))overset(Delta)underset(H_(2)O)rarrunderset("methyl ALCOHOL")(2CH_(3)OH)`
`CH_(3)OH+(O)(K_(2)Cr_(2)O_(7)//dil.H_(2)SO_(4))/(Delta)underset("formic acid")(HCOOH)`
21.

Dimethyl cadmium and acetyl chloride produces

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acetone
t-butyl ALCOHOL
`2^(@)` - propyl alcohol
n- propyl alcohol

ANSWER :A
22.

Dimethyl ether and ethyl alcohol are

Answer»

Metamers
Homologues
Functional ISOMERS
Position isomers

Solution :`CH_(3)-O-CH_(3)` and `C_(2)H_(5)OH` are functional isomers.
23.

Dimerisation of NO_2 gives

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`N_(2)O_(4)`
`N_(2)O`
`N_(2)O_(2)`
`N_(3)O_(6)`

Answer :A
24.

Dimer acetic acid in benzene is in equilibrium with acetic acid at a particular condition of temperature and pressure. If half of the dimer molecules are hypothetically separated out then

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Osmotic PRESSURE of the solution reduces
FREEZING point of the soluion reduces
BOILING point of the solution reduces
VAPOUR pressure of the soluteion reduces

Solution :(a,b) are both correct answer.
25.

Dilution process of different aqueous solution , with water are given in List-I. The effects of dilution of the solutions on [H^(+)] are given in List-II. (Note : Degree of dissociation (alpha) of weak acid and weak base is ltlt 1, degree of hydrolysis of salt lt lt 1 , [H^(+)] represents the concentration of H^(+) ions) |{:(,"List-I",,"List -II"),((P),"(10 mL of 0.1 M NaOH+20 mL of 0.1 acetic acid)dilutes to 60 mL",(1),"The value of "[H^(+)]" does not change on dilution"),((Q),"(20 mL of 0.1 M NaOH + 20 mL of 0.1 M acetic acid)diluted to 80 mL",(2),"The value of "[H^(+)]" change to half of its initial value on dilution"),((R ),"(20 mL of 0.1 M HCl + 20 mL of 0.1 M ammonia solution)diluted to 80 mL",(3),"The value of "[H^(+)]" change to two times of its initial value on dilution"),((S),"10 mL saturated solution of "Ni(OH)_(2)" in equilibrium with excess solid "Ni(OH)_(2)" is ",(4),"The value of "[H^(+)]" changes to "(1)/(sqrt(2))" times of its initial value on dilution"),(,"diluted to 20 mL (solid "Ni(OH)_(2)" is still present after dilution)",,),(,,(5),"The value of "[H^(+)]" changes to "sqrt(2)" times of its initial value on dilution"):}|

Answer»


SOLUTION :`P to 1, Q to 5, R to 4, S to 1`
P. `underset("0.1M, 20ml")(CH_(3)COOH)+underset("0.1M, 10ML")(NaOH)to CH_(3)COONa+H_(2)O`
`pH=pKa rArr [H^(+)]` will not change on dilution correct match : F - 1
Q. `{:(underset("0.1M, 20ml")(CH_(3)COOH)+underset("0.1M, 20ml")(NaOH)to CH_(3)COONa+H_(2)O),(""- ""-"0.05M"):}`
`[OH^(-)]=sqrt(K_(H)C)=sqrt(((k_(w))/(k_(a))C))`
`[H^(+)]_(1)=sqrt((k_(w)k_(a))/(C))`
`([H^(+)]_(2))/([H^(+)]_(1))=sqrt((C_(1))/(C_(2)))=sqrt((0.05)/(0.025))=sqrt(2)`
Correct match : Q-5
R. `underset("0.1M, 20ml")(NH_(4)OH)+underset("0.1M, 20ml")(HCl)to underset(0.05M)(NH_(4)Cl)`
`[H^(+)]=sqrt(K_(H)C)`
`([H^(+)]_(2))/([H^(+)]_(1))=sqrt((C_(2))/(C_(1)))=(1)/(sqrt(2))`
Correct match : R-4
S. Because of dilution solubility does not change so `[H^(+)]` = constant.
26.

Dilute solutions of H_2O_2 cannot be concentrated by

Answer»

VACUUM distillation
treatment with `P_2O_5`
fractional CRYSTALLIZATION at lower temperatures
careful and slow EVAPORATION in a shallow dish.

Solution :`P_2O_5` is not used for this PURPOSE.
27.

Dilute soluion so boric acid is used as

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ANTIBIOTIC
antiseptic
sadative
hypnotic

Answer :B
28.

Dilute nitric acid on reaction with silver liberates:

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NO GAS
`NO_(2)` gas
`N_(2)` gas
`O_(2)` gas

Answer :A
29.

Dilute nitric acid react with copper to give,

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NO
`N_(2)O`
`NO_(2)`
`N_2O_5`

ANSWER :A
30.

Dilute hydrochloric acid solution cannot be concentrated by boiling beyond:

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`11%`
`22%`
`33%`
`44%`

ANSWER :B
31.

Dilute H_(2)SO_(4) can be used in groupof dil HCI

Answer»


Solution :HCI COMMON `H^(Theta)` iondecreases ionsionof `H_(@)S` giving less `[S^(Theta)]` that canpercipitate group II tosalphides .But `H_(2)SO_(4)` athough a good source of `H^(theta)` , will precipitate `Pb^(2+),Zn^(2+),Ba^(2+),Ca^(2+),Se^(2+)` ATC as their sulphate HENCE true
32.

Dilute HNO_3 reacts with limestone to yield:

Answer»

`CA(OH)_2. Ca(NO_3)_2`
`CaO.Ca(NO_3)_2`
`2CaO.Ca(NO_3)_2`
NONE of these

Answer :D
33.

Dilute aqueous KMnO_4 , at room temperature reacts with R-CH=CH-R to give

Answer»

R-CHO
R-COOH
RCHOH-CHOHR
`CO_2+H_2O`

Solution :`R-CH=CH-Runderset"room TEMP"overset("dilaqueous" KMnO_4)to underset("(Alcohol)")(R-undersetunderset(OH)(|)C-undersetunderset(OH)(|)CH-R) `
`R-CH=CH-Runderset"HEAT"overset("conc." KMnO_4)to R-COOH+R-COOH`
34.

Dilute aqueous KMnO_(4) at room temperature reactswith R-CH= CH-R to give

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`R-CHO`
`RCHOH-CHOHR`
`R-COOH`
`(CO_(2)+H_(2)O)`

ANSWER :B
35.

Dilute alkaline solution of KMnO_4 is called :

Answer»

Baeyer.s reagent
Fenton.s reagent
Mayer.s reagent
Grignard.s reagent

Answer :A
36.

Dilithium is crucial to the propulsion system of some starships. Dilithium is fomred by the adhesionof two lithium atoms in the gas phase: Li(g)+Li(g)toLi_(2)(g) The enthalpy of formation of dilithium is not easily measurable by direct means. However, th following thermochemicalparameters are known. DeltaH_(f)^(@) of Li_(g)=150kJ//mol IE of Li_(g)=5eV//"atom"[1eV//"atom"=100kJ//mol] BE of Li_((g))^(+)=130kJ//mol IE of Li_(2(g))=5eV//"molecule" [IE= ionisation energy] [BE= bond energy] Q. What is DeltaH_(f)^(@) of Li_(2(g))?

Answer»

`130kJ//mol`
`170kJ//mol`
`270kJ//mol`
`-270kJ//mol`

ANSWER :A
37.

Dihydroxyacetone (CH_2OH . CO . CH_2OH) has the general formula of carbohydrate but not included in this class due to :

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It does not contain polyhydroxy gp.
It does not contain ALDEHYDE gp.
It is not OPTICALLY ACTIVE
All

Answer :C
38.

Dihydroxy diethyl terephthalate is obtained byethylene glycol and what ?

Answer»

PHBV
DMT
HDPE
PVC

Answer :B
39.

Dihydrogen reacts with CO at 700 k in presence of a cataylst ZnO//Cr_(2)O_(3)to form

Answer»

METHANE
ethanol
METHANOL
METHANAL

ANSWER :C
40.

Dihydrogen gas used in Haber's process is produced by reacting methane from natural gas with high temperature steam. The first stage of two stage reaction involves the formation of CO and H_(2). In second stage, CO formed in first stage is reacted with more steam in water gas shift reaction. CO(g)+H_(2)O(g)hArr CO_(2)(g)+H_(2)(g) If a reaction vessel at 400^(@)C is charged with an equimolar mixture of CO and steam such that p_(CO)=p_(H_(2)O)=4.0 bar, what will be the partial pressure of H_(2) at equilibrium? K_(p)=10.1 at 400^(@)C.

Answer»

<P>

Solution :Let the PARTIAL pressure of `H_(2)` at equilibrium be 'p' bar. So, at equilibrium the partial pressures of the species involved in equilibrium will be as follows:
`{:(,CO(g),+,H_(2)O(g),HARR,CO_(2)(g),+,H_(2)(g)),("Initial pressure (bar)",4.0,,4.0,,,,),("Equilibrium pressure (bar)",4-p,,4-p,,p,,p):}`
For this reaction,
`K_(p)=(p_(CO_(2))xxp_(H_(2)))/(p_(CO)xxp_(H_(2)O))=(pxxp)/((4-p)(4-p))=10.1`
or, `(p)/(4-p)=3.178 or, p=(4xx3.178)/(4.178)=3.04`
`therefore` The partial pressure of `H_(2)` at equilibrium=3.04 bar.
41.

Dihydrogen has:

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TWO ISOTOPES and no isomers
Three isotopes and two NUCLEAR isomers
Threeisotopes and two OPTICAL isomers
Two isotopes and two genometrical isomers

Answer :B
42.

Dihydrogen forms three types of hydrides. (I) hydrides are formed by alkali metals and alkaline earth metals. (ii) hydrides are formed by non-metals and (iii) hydrides are formed by d-and f-block elements at elevated tempreature. Complex metal hydrides such as (iv) and (v) are powerful reducing agents.

Answer»

(i)= Covalent (ii)=Molecular (III) = Saline(iv) NAH , (v) LIH
(i)= Molecular (ii)= Covalent (iii)Ionic(iv)= `LiAlH_(4),(v)= NaBH_(4)`
(i)= Ionic (ii) = Covalent (iii)=Interstitial(iv)= `LiAlH_(4)`(v)= `NaBH_(4)`
(i) = Ionic (ii) = Saline Interstitial(iii)= `LiAlH_(4)` (iv)=`NaBH_(4)`

ANSWER :C
43.

Dihedral angle in staggerred form of ethane is

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`0^(@)`
`120^(@)`
`60^(@)`
`180^(@)`

Answer :3
44.

Digestion of fat in intestine is aided by :

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DIFFUSION
PROTECTION
PEPTIZATION
Emulsification

Answer :D
45.

What is Van't Hoff equation for osmotic pressure ?

Answer»

Solution :(i) Boyle-Van.t Hoff LAW :
" TEMPERATURE remaining constant , the osmotic pressure` pi` of a DILUTE solution is directly PROPORTIONAL to the concentration of the solution ."
`rArr pi prop C or,pi prop 1/V rArr piV = K.`
46.

Difine nolality. What are its units ?

Answer»

SOLUTION :Moles/kg.
47.

Difine Van't Hoff laws of Osmotic pressure.

Answer»

Solution :(i) Boyle-Van.t Hoff law :
" TEMPERATURE remaining CONSTANT , the osmotic pressure` PI` of a dilute solution is directly proportional to the concentration of the solution ."
`rArr pi prop C or,pi prop 1/V rArr piV = K.`
48.

Difine electrophoresis.

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Solution :The MOVEMENT of COLLOIDAL particles under the influence of an ELECTRIC FIELD is CALLED electrophoresis.
49.

Difine calcinationwith one example.

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SOLUTION :
50.

Difine Azeotropes and explain briefgly minimum boiling azeotrope by taking suitable example.

Answer»

SOLUTION :For ANSWER, CONSULT SECTION 7.