Explore topic-wise MCQs in Joint Entrance Exam - Main (JEE Main).

This section includes 11242 Mcqs, each offering curated multiple-choice questions to sharpen your Joint Entrance Exam - Main (JEE Main) knowledge and support exam preparation. Choose a topic below to get started.

551.

Arrange the following in increasing order of \[pH\,\,KN{{O}_{3}}(aq),\,C{{H}_{3}}COON(aq),\]\[N{{H}_{4}}Cl(aq),\,{{C}_{6}}{{H}_{5}}COON{{H}_{4}}(aq)\]

A. \[C{{H}_{3}}COONa<{{C}_{6}}{{H}_{5}}COON{{H}_{4}}\]\[<N{{H}_{4}}Cl<KN{{O}_{3}}\]
B. \[KN{{O}_{3}}<N{{H}_{4}}C<C{{H}_{3}}COONa\]\[<{{C}_{6}}{{H}_{5}}COONa\]
C. \[N{{H}_{4}}Cl<KN{{O}_{3}}<C{{H}_{3}}COONa\]\[<{{C}_{6}}{{H}_{5}}COON{{H}_{4}}\]
D. \[N{{H}_{4}}Cl<KN{{O}_{3}}<{{C}_{6}}{{H}_{5}}COON{{H}_{4}}\]\[<C{{H}_{3}}COONa\]
Answer» E.
552.

The number of possible alcoholic isomers for \[{{C}_{4}}{{H}_{10}}O\] are [DPMT 1984; MNR 1986]

A. 4
B. 2
C. 3
D. 5
Answer» B. 2
553.

At \[30{}^\circ C\] the solubility of \[A{{g}_{2}}C{{O}_{3}}\] \[({{K}_{SP}}=8\times {{10}^{-12}})\] would be greatest in one litre of:

A. \[0.05M\,\,N{{a}_{2}}C{{O}_{3}}\]
B. \[0.05M\,AgN{{O}_{3}}\]
C. Pure water
D. \[0.05M\,{{K}_{2}}C{{O}_{3}}\]
Answer» D. \[0.05M\,{{K}_{2}}C{{O}_{3}}\]
554.

A mixture of weak acid is \[0.1\text{ }M\] in \[HCOOH\] \[({{K}_{a}}=1.8\times {{10}^{-4}})\] and \[0.1\text{ }M\] in \[HOCN\,\,({{K}_{a}}=3.1\times {{10}^{-4}})\] Hence, \[[{{H}_{3}}{{O}^{\oplus }}]\] is

A. \[7.0\times {{10}^{-3}}M\]
B. \[4.1\times {{10}^{-4}}M\]
C. \[0.20M\]
D. \[4.1\times {{10}^{-3}}M\]
Answer» B. \[4.1\times {{10}^{-4}}M\]
555.

The double helical structure of DNA was proposed by [KCET 1998]

A. Watson and Crick
B. Meicher
C. Emil Fischer
D. Khorana
Answer» B. Meicher
556.

The solubility of \[AgCl\] in water at \[25{}^\circ C\] is \[1.79\times {{10}^{-3}}g/L\]. The \[{{K}_{sp}}\] of \[AgCl\] at \[25{}^\circ C\] is

A. \[1.68\times {{10}^{-12}}\]
B. \[1.55\times {{10}^{-10}}\]
C. \[12.4\times {{10}^{-8}}\]
D. \[1.73\times {{10}^{-14}}\]
Answer» C. \[12.4\times {{10}^{-8}}\]
557.

If the de-Broglie wavelength of a particle mass m is 100 times its velocity, then its value in terms of its mass (m) and Planck's constant (h) is

A. \[\frac{1}{10}\sqrt{\frac{m}{h}}\]
B. \[10\sqrt{\frac{h}{m}}\]
C. \[\frac{1}{10}\sqrt{\frac{h}{m}}\]
D. \[10\sqrt{\frac{m}{h}}\]
Answer» C. \[\frac{1}{10}\sqrt{\frac{h}{m}}\]
558.

Approximate atomic weight of an element is 26.89. If its equivalent weight is 8.9, the exact atomic weight of element would be [DPMT 1984]

A. 26.89
B. 8.9
C. 17.8
D. 26.7
Answer» E.
559.

A metallic element has a cubic lattice. Each edge of the unit cell is \[2{{A}^{0}}\]. The density of the metal is \[2\text{ }g\text{ }c{{m}^{-3}}\]. The unit cells in 200 g of the metal are

A. \[1\times {{10}^{25}}\]
B. \[1\times {{10}^{24}}\]
C. \[1\times {{10}^{22}}\]
D. \[1\times {{10}^{20}}\]
Answer» B. \[1\times {{10}^{24}}\]
560.

Which of following is an example of ionic crystalline solid?

A. Diamond
B. LiF
C. Li
D. Silicon
Answer» C. Li
561.

Which of the following statements about amorphous solids

A. They melt over a range of temperature
B. They are isotropic
C. There is no orderly arrangement of particles
D. They are rigid and incompressible
Answer» C. There is no orderly arrangement of particles
562.

The impure 6 g of NaCl is dissolved in water and then treated with excess of silver nitrate solution. The mass of precipitate of silver chloride is found to be 14 g. The % purity of NaCl solution would be:

A. 95%
B. 0.85
C. 75%
D. 0.65
Answer» B. 0.85
563.

A black sulphide is formed by the action of \[{{H}_{2}}S\] on [IIT 1978]

A. Cupric chloride
B. Cadmium chloride
C. Zinc chloride
D. Sodium chloride
Answer» B. Cadmium chloride
564.

Different colloidal particles of gold having different colours, obtained from different methods due to                                                 [MP PET 1989; UPSEAT 2001, 02; EAMCET 2003]

A. Variable valency of gold
B. Different concentration of gold particles
C. Different types of impurities
D. Different radius of colloidal particles
Answer» E.
565.

The acid which has a peroxy linkage is

A. Sulphurous acid
B. Pyrosulphuric acid
C. Dithionic acid
D. Caro's acid
Answer» E.
566.

In graphite, carbon atoms are joined together due to [AFMC 2002]

A. Ionic bonding
B. Vander Waal?s forces
C. Metallic bonding
D. Covalent bonding
Answer» E.
567.

\[Sb{{F}_{5}}\] reacts with \[Xe{{F}_{4}}\] to form an adduct. The shapes of cation and anion in the adduct are respectively:

A. square planar, trigonal bipyramidal
B. T-shaped, octahedral
C. square pyramidal, octahedral
D. square planar, octahedral
Answer» C. square pyramidal, octahedral
568.

Nitroethane can exhibit one of the following kind of isomerism [DCE 2004]

A. Metamerism
B. Optical activity
C. Tautomerism
D. Position isomerism
Answer» D. Position isomerism
569.

Which is not a property of solids               [MP PET 1995]

A. Solids are always crystalline in nature
B. Solids have high density and low compressibility
C. The diffusion of solids is very slow
D. Solids have definite volume
Answer» B. Solids have high density and low compressibility
570.

Glycerol has strong intermolecular bonding therefore it is            [RPET 2000]

A. Sweet
B. Reactive
C. Explosive
D. Viscous
Answer» E.
571.

\[5N\] \[{{H}_{2}}S{{O}_{4}}\] was diluted from 1 litre to 10 litres. Normality of the solution obtained is

A. 10 N
B. 5 N
C. 1 N
D. 0.5 N
Answer» E.
572.

When the following redox reaction is balanced, coefficient of \[{{H}^{+}}\] would be:  \[M{{n}^{2+}}+BiO_{3}^{-}+{{H}^{+}}\to B{{i}^{3+}}+MnO_{4}^{-}+{{H}_{2}}O\]

A. 3
B. 4
C. 7
D. 14
Answer» E.
573.

Consider the redox reaction : \[2S{{O}_{2}}O_{3}^{2-}+{{I}_{2}}\to {{S}_{4}}O_{6}^{2-}+2{{I}^{-}}\]

A. \[2S{{O}_{2}}O_{3}^{2-}\] gets oxidised to \[S{{O}_{4}}O_{6}^{2-}\]
B. \[S{{O}_{2}}O_{3}^{2-}\] gets reduced to \[{{S}_{4}}O_{6}^{2-}\]
C. \[{{I}_{2}}\] gets reduced to \[{{I}^{-}}\]
D. \[{{I}_{2}}\] gets oxidised to \[{{I}^{-}}\]
Answer» E.
574.

Which of the following are redox reactions?

A. \[\frac{1}{2}{{H}_{2}}+\frac{1}{2}{{I}_{2}}+HI\]
B. \[PC{{l}_{5}}\to PC{{l}_{3}}+C{{l}_{2}}\]
C. \[2CuS{{O}_{4}}+4KI\to C{{u}_{2}}{{I}_{2}}+2{{K}_{2}}S{{O}_{4}}+{{I}_{2}}\]
D. \[CaOC{{l}_{2}}\to C{{a}^{+2}}+OC{{l}^{-}}+C{{l}^{-}}\]
Answer» B. \[PC{{l}_{5}}\to PC{{l}_{3}}+C{{l}_{2}}\]
575.

The function of DNA in an organism is    [DCE 2003]

A. To assist in the synthesis of RNA molecule
B. To store information of heredity characteristics
C. To assist in the synthesis of proteins and polypeptides
D. All of these
Answer» E.
576.

Which category of salts of alkaline earth metals is not found in solid sate, but found in solution state?

A. Carbonates
B. Bicarbonates
C. Hydroxides
D. Sulphates
Answer» C. Hydroxides
577.

A metal, M forms chlorides in its +2 and +4 oxidation states. Which of the following statements about these chlorides is correct?

A. \[MC{{l}_{2}}\] is more ionic than \[MC{{l}_{4}}\]
B. \[MC{{l}_{2}}\] is more easily hydrolysed than \[MC{{l}_{4}}\]
C. \[MC{{l}_{2}}\] is more volatile than \[MC{{l}_{4}}\]
D. \[MC{{l}_{2}}\] is more soluble in anhydrous ethanol than \[MC{{l}_{4}}\]
Answer» B. \[MC{{l}_{2}}\] is more easily hydrolysed than \[MC{{l}_{4}}\]
578.

Number of sigma bonds in \[{{P}_{4}}{{O}_{10}}\] is

A. 6
B. 7
C. 17
D. 16
Answer» E.
579.

An isotope \[_{Y}{{A}^{X}}\] undergoes a series of \[m\]  alpha and \[n\] beta disintegration to form a stable isotope \[_{Y-10}{{B}^{X-32}}\].  The values of \[m\] and \[n\] are respectively              [MP PET 1995]

A. 6 and 8
B. 8 and 10
C. 5 and 8
D. 8 and 6
Answer» E.
580.

Which of the following is not a sex hormone [MP PMT 2000]

A. Testosterone
B. Estrone
C. Estradiol
D. Cortisone
Answer» E.
581.

The highest electrical conductivity of the following aqueous solutions is of                                           [AIEEE 2005]

A. 0.1 M acetic acid
B. 0.1 M chloroacetic acid
C. 0.1 M fluoroacetic acid
D. 0.1 M difluoroacetic acid
Answer» E.
582.

In Nessler's reagent for the detection of ammonia the active species is [Kerala (Med.) 2003]

A. \[H{{g}_{2}}C{{l}_{2}}\]
B. \[H{{g}^{2+}}\]
C. \[H{{g}_{2}}{{I}_{2}}\]
D. \[HgI_{4}^{2-}\]
Answer» E.
583.

Which of the following is not formed?

A. \[BeF_{4}^{2-}\]
B. \[BeF_{3}^{-}\]
C. \[BF_{4}^{-}\]
D. \[BF_{6}^{3-}\]
Answer» E.
584.

The enthalpy of vapourization of a liquid is \[30\,kJ\,mo{{l}^{-1}}\] and entropy of vapourization is \[75\,J\,mo{{l}^{-1}}K\]. The boiling point of the liquid at 1 atm is                 [IIT JEE (Screening) 2004]

A. 250K
B. 400K
C. 450K
D. 600K
Answer» C. 450K
585.

Simultaneous determination of exact position and momentum of an electron is                [BHU 1979]

A. Possible
B. Impossible
C. Sometimes possible sometimes impossible
D. None of the above
Answer» C. Sometimes possible sometimes impossible
586.

The gaseous endothermic reaction :  \[P+Q\to 3R\] at \[327{}^\circ C\] takes place spontaneously, because-

A. \[\Delta H<0;\,\Delta S<0\]
B. \[\Delta H>0;\,\Delta S>0\]
C. \[\Delta H<0;\,\Delta S>0\]
D. \[\Delta H>0;\,\Delta S<0\]
Answer» C. \[\Delta H<0;\,\Delta S>0\]
587.

For a gaseous reaction: \[2{{A}_{2}}(g)+5{{B}_{2}}(g)\to 2{{A}_{2}}{{B}_{5}}(g)\] at \[{{27}^{o}}C\] the heat change at constant pressure is found to be \[-\,50160\,J\]. Calculate the value of internal energy change \[(\Delta E)\]. Given that R = 8.314 J/K mol.

A. - 34689 J
B. - 37689 J
C. - 27689 J
D. - 38689 J
Answer» C. - 27689 J
588.

The difference between the heats of reaction at constant pressure and a constant volume for the reaction \[2{{C}_{6}}{{H}_{6\left( 1 \right)}}+15{{O}_{2(g)}}\xrightarrow{{}}12C{{O}_{2(g)}}+6{{H}_{2}}{{O}_{(I)}}\] in Kj is :

A. -7.43
B. 3.72
C. -3.72
D. 7.43
Answer» B. 3.72
589.

A compound AB whose electro negativity difference is 1.9. Atomic radius of A and B are 4 and \[2\,\overset{\text{o}}{\mathop{\text{A}}}\,\]. The distance between A & B means \[{{d}_{A-B}}\] is

A. \[6.72\,\overset{\text{o}}{\mathop{\text{A}}}\,\]
B. \[5.82\,\overset{\text{o}}{\mathop{\text{A}}}\,\]
C. \[6.9\,\overset{\text{o}}{\mathop{\text{A}}}\,\]
D. \[7.5\,\overset{\text{o}}{\mathop{\text{A}}}\,\]
Answer» C. \[6.9\,\overset{\text{o}}{\mathop{\text{A}}}\,\]
590.

The correct order of the metallic character is:

A. \[Na>Mg>Al>Si\]
B. \[Mg>Na>Al>Si\]
C. \[Al>Mg>Na>Si\]
D. \[Si>Al>Na>Mg\]
Answer» B. \[Mg>Na>Al>Si\]
591.

The gaseous HX molecule has a measured dipole moment of 4.0 D, which indicates that it is a very polar molecule. The separation between the nuclei in this molecule is \[2.67\times {{10}^{-8}}cm\] then the percentage ionic character in HX molecule:

A. 0.78
B. 0.3125
C. 0.5025
D. None of these
Answer» C. 0.5025
592.

Which one is used as a food preservative [MP PET 1989; KCET 1999]

A. Sodium acetate
B. Sodium propionate
C. Sodium benzoate
D. Sodium oxalate
Answer» D. Sodium oxalate
593.

Experimental evidence for the existence of the atomic nucleus comes from

A. Millikan's oil drop experiment
B. Atomic emission spectroscopy
C. The magnetic bending of cathode rays
D. Alpha scattering by a thin metal foil
Answer» E.
594.

When one mole of monoatomic ideal gas at T K undergoes adiabatic change under a constant external pressure of 1 atm changes volume from 1 litre to 2 litre. The final temperature in Kelvin would be             [IIT 2005]

A. \[\frac{T}{{{2}^{(2/3)}}}\]
B. T + \[\frac{2}{3\times 0.0821}\]
C. T
D. T - \[\frac{2}{3\times 0.0821}\]
Answer» E.
595.

The volume of \[\frac{N}{10}\] NaOH require to neutralise 100 ml of \[\frac{N}{25}\] HCl is [Pb. CET 2000]

A. 30 ml
B. 100 ml
C. 40 ml
D. 25 ml
Answer» D. 25 ml
596.

Increasing order of acid strength of halogen acid is  [DCE 2000]

A. \[HF<HCl<HBr<HI\]
B. \[HCl<HBr<HI<HF\]
C. \[HF<HI<HBr<HCl\]
D. None of these
Answer» B. \[HCl<HBr<HI<HF\]
597.

When primary amine is heated with \[C{{S}_{2}}\] in presence of excess mercuric chloride, it gives isothiocyanate. This reaction is called               [KCET 1998; CPMT 1997]

A. Hofmann bromide reaction
B. Hofmann mustard oil reaction
C. Carbylamine reaction
D. Perkin reaction
Answer» C. Carbylamine reaction
598.

The basis on the mode of their formation, the polymers can be classified              [MP PET 1999]

A. As addition polymers only
B. As condensation polymers only
C. As copolymers
D. Both as addition and condensation polymers
Answer» E.
599.

A reaction having equal activation energies for forward and reverse reaction has              [MP PMT 2002]

A. \[\Delta H=0\]
B. \[\Delta S=0\]
C. Zero order
D. None of these
Answer» B. \[\Delta S=0\]
600.

The bond angle between \[{{N}_{x}}\] in ice is closest to               [CPMT 1989; UPSEAT 2002]

A. \[{{120}^{o}}28'\]
B. \[{{60}^{o}}\]
C. \[{{90}^{o}}\]
D. \[{{105}^{o}}\]
Answer» E.