MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
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.
| 251. |
Number of electron having the quantum numbers \[n=4,\,\ell =0,\,s=-\frac{1}{2}\] in \[Z{{n}^{+2}}\] ion is/are: |
| A. | 1 |
| B. | 0 |
| C. | 2 |
| D. | 5 |
| Answer» C. 2 | |
| 252. |
Which solid will have the weakest intermolecular forces? |
| A. | Ice |
| B. | Phosphorus |
| C. | Naphthalene |
| D. | Sodium fluoride |
| Answer» B. Phosphorus | |
| 253. |
Which of the following intermolecular forces are present in ?nylon ? 66? [JIPMER 1997] |
| A. | Vander Waals |
| B. | Hydrogen bonding |
| C. | Dipole-dipole interaction |
| D. | None of these |
| Answer» C. Dipole-dipole interaction | |
| 254. |
The colloidal solution of gelatin is known [CPMT 1984] |
| A. | Solvent loving sol |
| B. | Reversible sol |
| C. | Hydrophilic colloids |
| D. | All of these |
| Answer» E. | |
| 255. |
Phenolphthalein does not act as an indicator for the titration between [NCERT 1976] |
| A. | \[KOH\] and \[{{H}_{2}}S{{O}_{4}}\] |
| B. | \[Ba{{\left( OH \right)}_{2}}\] and \[HCl\] |
| C. | \[NaOH\] and acetic acid |
| D. | Oxalic acid and \[KMn{{O}_{4}}\] |
| Answer» E. | |
| 256. |
A well stoppered thermos flask contains some ice cubes. This is an example of a [AIIMS 1992] |
| A. | Closed system |
| B. | Open system |
| C. | Isolated system |
| D. | Non-thermodynamic system |
| Answer» D. Non-thermodynamic system | |
| 257. |
Two consecutive irreversible first order reaction can be represented by \[A\xrightarrow[{}]{{{k}_{1}}}B\xrightarrow[{}]{{{k}_{2}}}C\].The rate equation for A is integrated to obtain\[{{[A]}_{t}}={{[A]}_{0}}{{e}^{-{{k}_{1}}t}}\] and \[{{[B]}_{t}}=\frac{{{k}_{1}}[{{A}_{0}}]}{{{k}_{2}}-{{k}_{1}}}[{{e}^{-{{k}_{1}}t}}-{{e}^{-{{k}_{2}}t}}]\].At what time will B be present in the greatest concentration? |
| A. | \[{{t}_{\max }}=\frac{1}{{{k}_{1}}+{{k}_{2}}}\ln \frac{{{k}_{2}}}{{{k}_{1}}}\] |
| B. | \[{{t}_{\max }}=\frac{1}{{{k}_{1}}+{{k}_{2}}}\ln \frac{{{k}_{2}}}{{{k}_{1}}}\] |
| C. | \[{{t}_{\max }}=\frac{1}{{{k}_{2}}+{{k}_{1}}}\ln \frac{{{k}_{1}}}{{{k}_{2}}}\] |
| D. | None of these |
| Answer» C. \[{{t}_{\max }}=\frac{1}{{{k}_{2}}+{{k}_{1}}}\ln \frac{{{k}_{1}}}{{{k}_{2}}}\] | |
| 258. |
Which of the following solutions has highest osmotic pressure [CPMT 1977] |
| A. | \[1\,M\,NaCl\] |
| B. | 1 M urea |
| C. | 1 M sucrose |
| D. | 1 M glucose |
| Answer» B. 1 M urea | |
| 259. |
A solid compound 'X' on heating gives \[C{{O}_{2}}\] gas and a residue. The residue mixed with water forms 'Y'. On passing an excess of \[C{{O}_{2}}\] through 'Y' water, a clear solution 'Z', is obtained. On boil. 'Z', compound 'X' is reformed. The compound 'X' is |
| A. | \[Ca{{(HC{{O}_{3}})}_{2}}\] |
| B. | \[CaC{{O}_{3}}\] |
| C. | \[N{{a}_{2}}C{{O}_{3}}\] |
| D. | \[{{K}_{2}}C{{O}_{3}}\] |
| Answer» C. \[N{{a}_{2}}C{{O}_{3}}\] | |
| 260. |
It is possible to distinguish between optical isomers by [Manipal MEE 1995; AFMC 1995] |
| A. | Infrared spectroscopy |
| B. | Mass spectrometry |
| C. | Melting point determination |
| D. | Polarimetry |
| Answer» E. | |
| 261. |
The isomerism exhibited by alkyl cyanide and alkyl isocyanide is [AFMC 1995, 97] |
| A. | Functional |
| B. | Positional |
| C. | Tautomerism |
| D. | Metamerism |
| Answer» B. Positional | |
| 262. |
Which of the following is the best description for the behaviour of bromine in the reaction given below? \[{{H}_{2}}O+B{{r}_{2}}\to HOBr+HBr\] |
| A. | Proton acceptor only |
| B. | Both oxidized and reduced |
| C. | Oxidized only |
| D. | Reduced only |
| Answer» C. Oxidized only | |
| 263. |
A 0.1 N solution of \[N{{a}_{2}}C{{O}_{3}}\] is titrated with 0.1 N \[HCl\] solution. The best indicator to be used is [NCERT 1971; DPMT 1983; AFMC 1992; CPMT 1983, 97] |
| A. | Potassium ferricyanide |
| B. | Phenolphthalein |
| C. | Methyl red |
| D. | Litmus paper |
| Answer» D. Litmus paper | |
| 264. |
The number of significant figures in \[6.02\times {{10}^{23}}\]is |
| A. | 23 |
| B. | 3 |
| C. | 4 |
| D. | 26 |
| Answer» C. 4 | |
| 265. |
A metal surface is exposed to solar radiations [DPMT 2005] |
| A. | The emitted electrons have energy less than a maximum value of energy depending upon frequency of incident radiations |
| B. | The emitted electrons have energy less than maximum value of energy depending upon intensity of incident radiation |
| C. | The emitted electrons have zero energy |
| D. | The emitted electrons have energy equal to energy of photos of incident light |
| Answer» B. The emitted electrons have energy less than maximum value of energy depending upon intensity of incident radiation | |
| 266. |
The reaction \[C{{H}_{4}}+C{{l}_{2}}\underset{{}}{\mathop{\xrightarrow{\text{uv light}}}}\,C{{H}_{3}}Cl+HCl\] is an example of [CBSE PMT 1999, 2002] |
| A. | Addition reactions |
| B. | Substitution reaction |
| C. | Elimination reaction |
| D. | Rearrangement reaction |
| Answer» C. Elimination reaction | |
| 267. |
An aqueous solution of oxalic acid dehydrate contains its 6.3 g in 250 mL. The volume of \[0.1N\] NaOH required to completely neutralize 10 mL of this solution |
| A. | 4 mL |
| B. | 20 mL |
| C. | 2 mL |
| D. | 40 mL |
| Answer» E. | |
| 268. |
What will be the oxidation number of I in the \[K{{I}_{3}}\]? |
| A. | \[-\frac{1}{3}\] |
| B. | \[-\frac{1}{4}\] |
| C. | 4 |
| D. | 3 |
| Answer» B. \[-\frac{1}{4}\] | |
| 269. |
Oxidation number of cobalt in \[[Co{{(N{{H}_{3}})}_{6}}]C{{l}_{2}}Br\] is - |
| A. | 6 |
| B. | zero |
| C. | 3 |
| D. | 2 |
| Answer» D. 2 | |
| 270. |
Sodium carbonate cannot be used in place of ammonium carbonate for the precipitation of the fifth group radicals because [AIIMS 1980] |
| A. | Sodium ions interfere with the detection of fifth group radicals |
| B. | Concentration of carbonate ions is very low |
| C. | Sodium will react with acidic radicals |
| D. | Magnesium will be precipitated |
| Answer» E. | |
| 271. |
The angular momentum of an electron depends on |
| A. | Principal quantum number |
| B. | Azimuthal quantum number |
| C. | Magnetic quantum number |
| D. | All of these |
| Answer» C. Magnetic quantum number | |
| 272. |
In a multi-electron atom, which of the following orbitals described by the three quantum members will have the same energy in the absence of magnetic and electric fields (1) \[n=1,\,l=0,\,m=0\] (2) \[n=2,\,l=0,\,m=0\] (3) \[n=2,\,l=1,\,m=1\] (4) \[n=3,\,l=2,\,m=0\] (5) \[n=3,\,l=2,\,m=0\] |
| A. | (1) and (2) |
| B. | (2) and (3) |
| C. | (3) and (4) |
| D. | (4) and (5) |
| Answer» E. | |
| 273. |
A large increase in the rate of a reaction for a rise in temperature is due to [EAMCET 1980; MP PET 1995] |
| A. | The decrease in the number of collisions |
| B. | The increase in the number of activated molecules |
| C. | The shortening of the mean free path |
| D. | The lowering of the activation energy |
| Answer» C. The shortening of the mean free path | |
| 274. |
An aerosol is a [UPSEAT 2004] |
| A. | Dispersion of a solid or liquid in a gas |
| B. | Dispersion of a solid in a liquid |
| C. | Dispersion of a liquid in a liquid |
| D. | Solid solution |
| Answer» B. Dispersion of a solid in a liquid | |
| 275. |
List-I and List-II contains four entries each. Entries of List-I are to be matched with some entries of List-II. One or more than one entries of List-I may have the matching with the same entries of List-II. List-I List-II [a] Rock salt structure (p) General formula is AB [b] Zinc blende structure (q) General formula is \[A{{B}_{3}}\] [c] Fluorite structure (r) General formula is \[{{A}_{2}}B\] [d] Anti fluorite structure (s) General formula is \[A{{B}_{2}}\] |
| A. | A-p, B-p, C-s, D-r |
| B. | A-q, B-q, C-p, D-s |
| C. | A-r, B-p, C-r, D-s |
| D. | A-s, B-s, C-p, D-q |
| Answer» B. A-q, B-q, C-p, D-s | |
| 276. |
When \[KBr\] is treated with conc. \[{{H}_{2}}S{{O}_{4}}\] a reddish-brown gas is evolved. The evolved gas is [EAMCET 1978] |
| A. | Bromine |
| B. | Mixture of bromine and \[HBr\] |
| C. | \[HBr\] |
| D. | \[N{{O}_{2}}\] |
| Answer» B. Mixture of bromine and \[HBr\] | |
| 277. |
When \[{{H}_{2}}S\]gas is passed through the HCl containing aqueous solutions of \[CuC{{l}_{2}}\], \[HgC{{l}_{2}}\], \[BiC{{l}_{3}}\] and \[CoC{{l}_{2}}\], which does not precipitate out [MP PMT 2002] |
| A. | \[CuS\] |
| B. | \[HgS\] |
| C. | \[B{{i}_{2}}{{S}_{3}}\] |
| D. | \[CoS\] |
| Answer» E. | |
| 278. |
Which one of the following characteristics is not correct for physical adsorption [AIEEE 2003] |
| A. | Adsorption on solids is reversible |
| B. | Adsorption increases with increase in temperature |
| C. | Adsorption is spontaneous |
| D. | Both enthalpy and entropy of adsorption are negative |
| Answer» C. Adsorption is spontaneous | |
| 279. |
Maximum number of hydrogen bonding in \[{{H}_{2}}O\] is [DCE 2004; MP PET 2004; MP PMT 2004; BHU 2004] |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» E. | |
| 280. |
The low density of ice compared to water is due to [Pb. CET 2004] |
| A. | Induced dipole-induced dipole interactions |
| B. | Dipole-induced dipole interaction |
| C. | Hydrogen bonding interactions |
| D. | Dipole-dipole interactions |
| Answer» D. Dipole-dipole interactions | |
| 281. |
When \[C{{O}_{2}}\] is passed into lime water it turns milky. When excess of \[C{{O}_{2}}\] is passed, milkyness disappears because |
| A. | Reaction is reversed |
| B. | Water soluble \[Ca{{(HC{{O}_{3}})}_{2}}\] is formed |
| C. | Vaporisable calcium derivative is formed |
| D. | None of these |
| Answer» C. Vaporisable calcium derivative is formed | |
| 282. |
The number of significant figures in 60.0001 is [Pb. CET 2000] |
| A. | 5 |
| B. | 6 |
| C. | 3 |
| D. | 2 |
| Answer» C. 3 | |
| 283. |
If a strip of \[Cu\] metal is placed in a solution of ferrous sulphate [NCERT 1974; CPMT 1977; MP PET 2000] |
| A. | Copper will precipitate out |
| B. | Iron will precipitate out |
| C. | Copper will dissolve |
| D. | No reaction will take place |
| Answer» E. | |
| 284. |
On passing \[{{H}_{2}}S\] black ppt. of II group is obtained. The mixture may not contain [CPMT 1989] |
| A. | \[P{{b}^{++}}\] |
| B. | \[C{{d}^{++}}\] |
| C. | \[H{{g}^{++}}\] |
| D. | \[C{{u}^{++}}\] |
| Answer» C. \[H{{g}^{++}}\] | |
| 285. |
In the following sequence of reaction, identify the compounds (A), (B) (C) and (D): \[\underset{Solution}{\mathop{N{{a}_{2}}C{{O}_{3}}}}\,\xrightarrow{S{{O}_{2}}}(A)\xrightarrow{N{{a}_{2}}C{{O}_{3}}}\] \[(B)\xrightarrow[Heat]{S}(C)\xrightarrow{AgN{{O}_{3}}}(D)\] |
| A. | \[N{{a}_{2}}S{{O}_{3}},NaHS{{O}_{3}},N{{a}_{2}}S,A{{g}_{2}}S\] |
| B. | \[NaHS{{O}_{3}},N{{a}_{2}}S{{O}_{3}},N{{a}_{2}}{{S}_{2}}{{O}_{3}},A{{g}_{2}}S\] |
| C. | \[NaHS{{O}_{3}},N{{a}_{2}}S{{O}_{4}},N{{a}_{2}}S,A{{g}_{2}}O\] |
| D. | \[N{{a}_{2}}S{{O}_{3}},N{{a}_{2}}S{{O}_{4}},N{{a}_{2}}{{S}_{2}}{{O}_{3}},Ag\] |
| Answer» C. \[NaHS{{O}_{3}},N{{a}_{2}}S{{O}_{4}},N{{a}_{2}}S,A{{g}_{2}}O\] | |
| 286. |
In known elements, the maximum number is of [CPMT 1985] |
| A. | Metals |
| B. | Non-metals |
| C. | Metalloids |
| D. | None of these |
| Answer» B. Non-metals | |
| 287. |
The velocity of neutrons in nuclear reactor is slowed down by |
| A. | Heavy water \[({{D}_{2}}O)\] |
| B. | Ordinary water \[({{H}_{2}}O)\] |
| C. | Zinc rod |
| D. | Fused caustic soda |
| Answer» B. Ordinary water \[({{H}_{2}}O)\] | |
| 288. |
The statement ? The mass of a gas dissolved in a given mass of a solvent at any temperature is proportional to the pressure of the gas above the solvent? is [AMU 2002] |
| A. | Dalton's Law of Partial Pressures |
| B. | Law of Mass Action |
| C. | Henry's Law |
| D. | None of these |
| Answer» D. None of these | |
| 289. |
Gold number is [MP PET/PMT 1988] |
| A. | The number of mg of lyophilic colloid which should be added to 10 ml of ferric hydroxide sol so as to prevent its coagulation by the addition of 1 ml of 10% sodium chloride solution |
| B. | The number of mg of lyophilic colloid which should be added to 10 ml of standard gold sol so as to prevent its coagulation by the addition of 1 ml of 10% \[NaCl\] |
| C. | The mg of gold salt to be added to a lyophilic colloid to coagulate it |
| D. | The mg of an electrolyte required to coagulate a colloid |
| Answer» C. The mg of gold salt to be added to a lyophilic colloid to coagulate it | |
| 290. |
Which of the following ions can cause coagulation of proteins [KCET 2000] |
| A. | \[A{{g}^{+}}\] |
| B. | \[N{{a}^{+}}\] |
| C. | \[M{{g}^{++}}\] |
| D. | \[C{{a}^{++}}\] |
| Answer» B. \[N{{a}^{+}}\] | |
| 291. |
The most basic among these hydroxides, is [MP PMT 2003] |
| A. | \[Be\,{{(OH)}_{2}}\] |
| B. | \[Mg\,{{(OH)}_{2}}\] |
| C. | \[Ca\,{{(OH)}_{2}}\] |
| D. | \[Ba\,{{(OH)}_{2}}\] |
| Answer» E. | |
| 292. |
Pb(CH3COO)2 gives?.colour with H2S [DPMT 2000] |
| A. | Orange |
| B. | Red |
| C. | Black |
| D. | White |
| Answer» D. White | |
| 293. |
A hydrogen electrode placed in a buffer solution of \[C{{H}_{3}}COONa\] and acetic acid in the ratio x : y and y : x has electrode potential value \[{{E}_{1}}\] volts and \[{{E}_{2}}\] volts, respectively at \[\text{25}{}^\circ \text{C}\]. The \[p{{K}_{a}}\] value of acetic acid is (\[{{E}_{1}}\] and \[{{E}_{2}}\] are oxidation potential): |
| A. | \[\frac{{{E}_{1}}+{{E}_{2}}}{0.118}\] |
| B. | \[\frac{{{E}_{2}}-{{E}_{1}}}{0.118}\] |
| C. | \[-\frac{{{E}_{1}}+{{E}_{2}}}{0.118}\] |
| D. | \[\frac{{{E}_{1}}-{{E}_{2}}}{0.118}\] |
| Answer» B. \[\frac{{{E}_{2}}-{{E}_{1}}}{0.118}\] | |
| 294. |
How much of NaOH is required to neutralize 1500 cm3 of 0.1 N HCl (At. wt. of Na = 23) [KCET (Med.) 2001] |
| A. | 4 g |
| B. | 6 g |
| C. | 40 g |
| D. | 60 g |
| Answer» C. 40 g | |
| 295. |
In the chromyl chloride test, the reagent used is [AMU 1983] |
| A. | \[{{K}_{2}}Cr{{O}_{4}}\] |
| B. | \[Cr{{O}_{3}}\] |
| C. | \[{{K}_{2}}C{{r}_{2}}{{O}_{7}}\] |
| D. | \[{{\left( N{{H}_{4}} \right)}_{2}}C{{r}_{2}}{{O}_{7}}\] |
| Answer» D. \[{{\left( N{{H}_{4}} \right)}_{2}}C{{r}_{2}}{{O}_{7}}\] | |
| 296. |
Which compound shows cis-trans isomerism [CPMT 2002] |
| A. | 1-butene |
| B. | 2-propene |
| C. | 2-butene |
| D. | Benzene |
| Answer» D. Benzene | |
| 297. |
Methyl acetate and propionic acid are [RPMT 2002] |
| A. | Functional isomer |
| B. | Structural isomer |
| C. | Stereoisomer |
| D. | Geometrical isomer |
| Answer» B. Structural isomer | |
| 298. |
If the \[Z{{n}^{2+}}/Zn\] electrode is diluted to 100 times then the change in e.m.f. [DPMT 2005] |
| A. | Increase of \[59\,mV\] |
| B. | Decrease of \[59\,mV\] |
| C. | Increase of \[29.5\,mV\] |
| D. | Decrease of \[29.5\,mV\] |
| Answer» B. Decrease of \[59\,mV\] | |
| 299. |
Least hindered rotation about carbon-carbon bond is observed in [RPMT 2000] |
| A. | Ethane |
| B. | Ethylene |
| C. | Ethyne |
| D. | Hexachloroethane |
| Answer» B. Ethylene | |
| 300. |
Which pair represents chain isomer [RPMT 2000] |
| A. | \[C{{H}_{3}}CHC{{l}_{2}}\] and \[ClC{{H}_{2}}C{{H}_{2}}Cl\] |
| B. | n-propyl alcohol and isopropyl alcohol |
| C. | 2-methyl-1 propanol and 2-Methyl-2 propanol |
| D. | 2-methyl butane and neopentane |
| Answer» E. | |