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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.
| 7251. |
The activation energy for a reaction is \[9.0\,K\,cal/mol.\] The increase in the rate constant when its temperature is increased from 298K to 308K is [JIPMER 2000] |
| A. | 63% |
| B. | 50% |
| C. | 100% |
| D. | 10% |
| Answer» B. 50% | |
| 7252. |
The temperature dependence of rate constant \[(k)\] of a chemical reaction is written in terms of Arrhenius equation, \[K=A.{{e}^{-E*/RT}}\]. Activation energy \[({{E}^{*}})\] of the reaction can be calculated by plotting [CBSE PMT 2003] |
| A. | \[\log \,k\,vs\,\frac{1}{\log \,T}\] |
| B. | \[k\,vs\,T\] |
| C. | \[k\,vs\,\frac{1}{\log \,T}\] |
| D. | \[\log \,k\,vs\,\frac{1}{T}\] |
| Answer» E. | |
| 7253. |
Activation energy of a chemical reaction can be determined by [CBSE PMT 1998; AFMC 1999; BHU 2000] |
| A. | Changing concentration of reactants |
| B. | Evaluating rate constant at standard temperature |
| C. | Evaluating rate constants at two different temperatures |
| D. | Evaluating velocities of reaction at two different temperatures |
| Answer» D. Evaluating velocities of reaction at two different temperatures | |
| 7254. |
The \[\Delta H\] value of the reaction \[{{H}_{2}}+C{{l}_{2}}\]⇌ \[2HCl\] is \[-44.12\,kcal\]. If \[{{E}_{1}}\] is the activation energy of the products, then for the above reaction [EAMCET 1997] |
| A. | \[{{E}_{1}}>{{E}_{2}}\] |
| B. | \[{{E}_{1}}<{{E}_{2}}\] |
| C. | \[{{E}_{1}}={{E}_{2}}\] |
| D. | \[\Delta H\] is not related to \[{{E}_{1}}\] and \[{{E}_{2}}\] |
| E. | None is correct |
| Answer» B. \[{{E}_{1}}<{{E}_{2}}\] | |
| 7255. |
If \[3A\to 2B,\] then the rate of reaction of \[+\frac{d(B)}{dt}\]is equal to [CBSE PMT 2002] |
| A. | \[+2\frac{d(A)}{dt}\] |
| B. | \[-\frac{1}{3}\frac{d(A)}{dt}\] |
| C. | \[-\frac{2}{3}\frac{d(A)}{dt}\] |
| D. | \[-\frac{3}{2}\frac{d(A)}{dt}\] |
| Answer» D. \[-\frac{3}{2}\frac{d(A)}{dt}\] | |
| 7256. |
For the reaction \[{{H}_{2}}(g)+{{I}_{2}}(g)\]⇌\[2HI(g)\], the rate of reaction is expressed as [CBSE PMT 1997; AIEEE 2002] |
| A. | \[-\frac{\Delta [{{I}_{2}}]}{\Delta t}=-\frac{\Delta [{{H}_{2}}]}{\Delta t}=\frac{1}{2}\frac{\Delta [HI]}{\Delta t}\] |
| B. | \[\frac{\Delta [{{I}_{2}}]}{\Delta t}=\frac{\Delta [{{H}_{2}}]}{\Delta t}=\frac{\Delta [HI]}{2\Delta t}\] |
| C. | \[\frac{\Delta [{{H}_{2}}]}{\Delta t}=\frac{1}{2}\frac{\Delta [{{I}_{2}}]}{\Delta t}=-\frac{\Delta [HI]}{\Delta t}\] |
| D. | None of these |
| Answer» B. \[\frac{\Delta [{{I}_{2}}]}{\Delta t}=\frac{\Delta [{{H}_{2}}]}{\Delta t}=\frac{\Delta [HI]}{2\Delta t}\] | |
| 7257. |
Carboxylic acids are more acidic than phenol and alcohol because of [Tamil Nadu CET 2001] |
| A. | Intermolecular hydrogen bonding |
| B. | Formation of dimers |
| C. | Highly acidic hydrogen |
| D. | Resonance stabilization of their conjugate base |
| Answer» E. | |
| 7258. |
In a set of the given reactions, acetic acid yielded a product C \[C{{H}_{3}}COOH+PC{{l}_{5}}\to A\underset{anh.\,AlC{{l}_{3}}}{\mathop{\xrightarrow{{{C}_{6}}{{H}_{6}}}}}\,\]\[B\underset{ether}{\mathop{\xrightarrow{{{C}_{2}}{{H}_{5}}MgBr}}}\,C\].Product C would be [CBSE PMT 2003] |
| A. | \[\overset{\overset{{{C}_{2}}{{H}_{5}}}{\mathop{|\,\,\,\,\,\,\,\,\,\,}}\,}{\mathop{C{{H}_{3}}-C(OH){{C}_{6}}{{H}_{5}}}}\,\] |
| B. | \[C{{H}_{3}}CH(OH){{C}_{2}}{{H}_{5}}\] |
| C. | \[C{{H}_{3}}CO{{C}_{6}}{{H}_{5}}\] |
| D. | \[C{{H}_{3}}CH(OH){{C}_{6}}{{H}_{5}}\] |
| Answer» B. \[C{{H}_{3}}CH(OH){{C}_{2}}{{H}_{5}}\] | |
| 7259. |
When \[C{{H}_{2}}=CH-COOH\] is reduced with \[LiAl{{H}_{4}}\], the compound obtained will be [AIEEE 2003] |
| A. | \[C{{H}_{3}}-C{{H}_{2}}-COOH\] |
| B. | \[C{{H}_{2}}=CH-C{{H}_{2}}OH\] |
| C. | \[C{{H}_{3}}-C{{H}_{2}}-C{{H}_{2}}OH\] |
| D. | \[C{{H}_{3}}-C{{H}_{2}}-CHO\] |
| Answer» C. \[C{{H}_{3}}-C{{H}_{2}}-C{{H}_{2}}OH\] | |
| 7260. |
An organic compound of molecular formula \[{{C}_{4}}{{H}_{10}}O\] does not react with sodium. With excess of \[HI,\] it gives only one type of alkyl halide. The compound is [SCRA 2001] |
| A. | Ethoxyethane |
| B. | 2-Methoxypropane |
| C. | 1-Methoxypropane |
| D. | 1-Butanol |
| Answer» B. 2-Methoxypropane | |
| 7261. |
Iodoform test is not given by [BHU 1995] |
| A. | Acetone |
| B. | Ethyl alcohol |
| C. | Acetic acid |
| D. | None of these |
| Answer» D. None of these | |
| 7262. |
The ortho/para directing group among the following is [AIIMS 2003] |
| A. | \[COOH\] |
| B. | \[CN\] |
| C. | \[COC{{H}_{3}}\] |
| D. | \[NHCOC{{H}_{3}}\] |
| Answer» E. | |
| 7263. |
The compound not soluble in acetic acid is [UPSEAT 2003; IIT-JEE 1986] |
| A. | \[CaC{{O}_{3}}\] |
| B. | \[CaO\] |
| C. | \[Ca{{C}_{2}}{{O}_{4}}\] |
| D. | \[Ca{{(OH)}_{2}}\] |
| Answer» D. \[Ca{{(OH)}_{2}}\] | |
| 7264. |
Identify the correct order of boiling points of the following compounds \[\underset{(1)}{\mathop{C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}C{{H}_{2}}OH}}\,\],\[\underset{(2)}{\mathop{C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}CHO}}\,\], \[\underset{(3)}{\mathop{C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}COOH}}\,\] [IIT-JEE (Screening) 2002] |
| A. | \[1>2>3\] |
| B. | \[3>1>2\] |
| C. | \[1>3>2\] |
| D. | \[3>2>1\] |
| Answer» C. \[1>3>2\] | |
| 7265. |
Benzoyl chloride is prepared from benzoic acid by [IIT-JEE (Screening) 2000] |
| A. | \[C{{l}_{2}},\,\,hv\] |
| B. | \[S{{O}_{2}}C{{l}_{2}}\] |
| C. | \[SOC{{l}_{2}}\] |
| D. | \[C{{l}_{2}},{{H}_{2}}O\] |
| Answer» D. \[C{{l}_{2}},{{H}_{2}}O\] | |
| 7266. |
When propionic acid is treated with aqueous sodium bicarbonate \[C{{O}_{2}}\] is liberated. The 'C' of \[C{{O}_{2}}\] comes from [IIT-JEE (Screening) 1999] |
| A. | Methyl group |
| B. | Carboxylic acid group |
| C. | Methylene group |
| D. | Bicarbonate |
| Answer» E. | |
| 7267. |
\[R-C{{H}_{2}}-C{{H}_{2}}OH\] can be converted into \[RC{{H}_{2}}C{{H}_{2}}COOH.\] The correct sequence of the reagents is [AIIMS 1997] |
| A. | \[PB{{r}_{3}},KCN,{{H}_{3}}{{O}^{+}}\] |
| B. | \[PB{{r}_{3}},KCN,{{H}_{2}}\] |
| C. | \[HCN,PB{{r}_{3}},{{H}^{+}}\] |
| D. | \[KCN,{{H}^{+}}\] |
| Answer» B. \[PB{{r}_{3}},KCN,{{H}_{2}}\] | |
| 7268. |
Hydrogenation of \[{{C}_{6}}{{H}_{5}}CHOH-COOH\] over \[Rh-A{{l}_{2}}{{O}_{3}}\] catalyst in methanol gives [Roorkee Qualifying 1998] |
| A. | \[{{C}_{6}}{{H}_{5}}C{{H}_{2}}COOH\] |
| B. | \[{{C}_{6}}{{H}_{11}}CHOHCOOH\] |
| C. | \[{{C}_{6}}{{H}_{5}}CHOHC{{H}_{2}}OH\] |
| D. | \[{{C}_{6}}{{H}_{11}}C{{H}_{2}}COOH\] |
| Answer» C. \[{{C}_{6}}{{H}_{5}}CHOHC{{H}_{2}}OH\] | |
| 7269. |
Ethyl ester\[\underset{\text{excess}}{\mathop{\xrightarrow{C{{H}_{3}}MgBr}}}\,P\]. The product P will be [IIT-JEE 2003] |
| A. | |
| B. | |
| C. | |
| D. | |
| Answer» B. | |
| 7270. |
Proteins fulfil several functions in living systems. An example of a protein which acts as a hormone is [KCET 1985] |
| A. | Casein |
| B. | Oxytocin |
| C. | Trypsin |
| D. | Keratin |
| Answer» C. Trypsin | |
| 7271. |
Insulin is a protein which plays the role of [KCET 1986] |
| A. | An antibody |
| B. | A harmone |
| C. | An enzyme |
| D. | A transport agent |
| Answer» C. An enzyme | |
| 7272. |
DNA multiplication is called [Kerala (Med.) 2000] |
| A. | Translation |
| B. | Transduction |
| C. | Transcription |
| D. | Replication |
| Answer» E. | |
| 7273. |
Chargaff's rule states that in an organism [CBSE PMT 2003] |
| A. | Amounts of all bases are equal |
| B. | Amount of adenine A is equal to that of thymine T and the amount of guanine G is equal to that of cytosine C |
| C. | Amount of adenine A is equal to that of guanine G and the amount of thymine T is equal to that of cytosine C |
| D. | Amount of adenine A is equal to that of cytosine C and the amount of thymine T is equal to guanine G |
| Answer» C. Amount of adenine A is equal to that of guanine G and the amount of thymine T is equal to that of cytosine C | |
| 7274. |
A sequence of how many nucleotides in messenger RNA makes a codon for an amino acid [CBSE PMT 2004] |
| A. | One |
| B. | Two |
| C. | Three |
| D. | Four |
| Answer» D. Four | |
| 7275. |
Sucrose molecule is made up of [KCET 2005] |
| A. | A gluco pyranose and a fructo pyranose |
| B. | A gluco pyranose and a fructo furanose |
| C. | A gluco furanose and a fructo pyranose |
| D. | A gluco furanose and a fructo furanose |
| Answer» C. A gluco furanose and a fructo pyranose | |
| 7276. |
The two forms of D-glucopyranose obtained from the solution of D-glucose are called [IIT JEE Screening 2005] |
| A. | Isomer |
| B. | Anomer |
| C. | Epimer |
| D. | Enantiomer |
| Answer» C. Epimer | |
| 7277. |
Ribose is an example of [KCET 1998] |
| A. | Ketohexose |
| B. | Aldopentose |
| C. | Disaccharide |
| D. | Aldohexose |
| Answer» C. Disaccharide | |
| 7278. |
A zwitter ion is [KCET 1989] |
| A. | A positively charged ion without a metal atom in it |
| B. | A negatively charged ion without metal atom in it |
| C. | An ion with positive and negative charges at different points on it |
| D. | A heavy ion with a small charge on it |
| Answer» D. A heavy ion with a small charge on it | |
| 7279. |
When glucose reacts with bromine water, the main product is [Pb. CET 2003; BHU 2004] |
| A. | Acetic acid |
| B. | Saccharic acid |
| C. | Glyceraldyhyde |
| D. | Gluconic acid |
| Answer» E. | |
| 7280. |
Alkyl benzene sulphonates can be conductivity used as detergents in hard water, unlike soaps, as [AMU 2002] |
| A. | They are highly soluble in water |
| B. | Their \[C{{a}^{++}}/M{{g}^{++}}\] salts are water soluble |
| C. | They are non-ionic |
| D. | Their \[C{{a}^{++}}/M{{g}^{++}}\] salts are insoluble in water |
| Answer» E. | |
| 7281. |
Subunits present in hemoglobin are [AIIMS 2003] |
| A. | 2 |
| B. | 3 |
| C. | 4 |
| D. | 5 |
| Answer» D. 5 | |
| 7282. |
Proteins do not respond to |
| A. | Biuret test |
| B. | Heller's ring test |
| C. | Ninhydrin test |
| D. | Lucas test |
| Answer» E. | |
| 7283. |
Which of the following is not an acidic amino acid |
| A. | Lysine |
| B. | Arginine |
| C. | Aspartic acid |
| D. | Histidine |
| Answer» D. Histidine | |
| 7284. |
Which one of the following is a polysaccharide [NDA 1999] |
| A. | Nylon |
| B. | Amylose |
| C. | Ribose |
| D. | Polyethylene |
| Answer» C. Ribose | |
| 7285. |
Starting with three different amino acid molecules, how many different tripeptide molecules are formed [Kerala PMT 1999; KCET 1999] |
| A. | 12 |
| B. | 9 |
| C. | 8 |
| D. | 6 |
| Answer» E. | |
| 7286. |
A compound of mol. wt. 180 is acetylated to give a compound of mol. wt. 390. The number of amino groups in the initial compound is [KCET 1996] |
| A. | 2 |
| B. | 4 |
| C. | 5 |
| D. | 6 |
| Answer» D. 6 | |
| 7287. |
The cell membranes are mainly composed of [CBSE PMT 2005] |
| A. | Carbohydrates |
| B. | Proteins |
| C. | Phospholipids |
| D. | Fats |
| Answer» C. Phospholipids | |
| 7288. |
The helical structure of protein is stabilized by [CBSE PMT 2004] |
| A. | Ether bonds |
| B. | Peptide bonds |
| C. | Dipeptide bonds |
| D. | Hydrogen bonds |
| Answer» E. | |
| 7289. |
The enzyme which hydrolyses triglycerides to fatty acids and glycerol is called [CBSE PMT 2004] |
| A. | Zymase |
| B. | Pepsin |
| C. | Maltase |
| D. | Lipase |
| Answer» E. | |
| 7290. |
Protein can be most easily removed from [UPSEAT 2000, 02] |
| A. | Alkanes |
| B. | Alkenes |
| C. | Alkynes |
| D. | Benzene |
| Answer» E. | |
| 7291. |
The number of molecules of ATP produced in the lipid metabolism of a molecule of palmitic acid is [CBSE PMT 1998] |
| A. | 130 |
| B. | 36 |
| C. | 56 |
| D. | 86 |
| Answer» B. 36 | |
| 7292. |
Vitamin \[{{B}_{12}}\] contains metal [Bihar MEE 1997; RPET 1999; Pb. PMT 1999; AFMC 2002; CBSE PMT 2003; CPMT 2003; MP PMT 2003] |
| A. | Ca (II) |
| B. | Zn (II) |
| C. | Fe (II) |
| D. | Co (III) |
| Answer» E. | |
| 7293. |
Pick out the unsaturated fatty acid from the following [KCET 2004; MHCET 2002] |
| A. | Stearic acid |
| B. | Lauric acid |
| C. | Oleic acid |
| D. | Palmitic acid |
| Answer» D. Palmitic acid | |
| 7294. |
Number of chiral carbons in \[\beta -D-(+)\]-glucose is [CBSE PMT 2004; MHCET 2004] |
| A. | Three |
| B. | Four |
| C. | Five |
| D. | Six |
| Answer» C. Five | |
| 7295. |
Mixture is heated with dil. \[{{H}_{2}}S{{O}_{4}}\] and the lead acetate paper turns black by the evolved gases. The mixture contains |
| A. | Sulphite |
| B. | Sulphide |
| C. | Sulphate |
| D. | Thiosulphate |
| Answer» C. Sulphate | |
| 7296. |
The brown ring test for NO2 and \[N{{O}_{3}}^{-}\]is due to the formation of complex ion with the formula [KCET (Eng./Med.) 2000; Kerala PMT 2004] |
| A. | \[{{\left[ Fe{{\left( {{H}_{2}}O \right)}_{6}} \right]}^{2+}}\] |
| B. | \[{{\left[ Fe\left( NO \right)\text{ }{{\left( CN \right)}_{5}} \right]}^{2+}}\] |
| C. | \[{{\left[ Fe{{\left( {{H}_{2}}O \right)}_{5}}NO \right]}^{2+}}\] |
| D. | \[{{\left[ Fe\left( {{H}_{2}}O \right)\text{ }{{\left( NO \right)}_{5}} \right]}^{2+}}\] |
| Answer» D. \[{{\left[ Fe\left( {{H}_{2}}O \right)\text{ }{{\left( NO \right)}_{5}} \right]}^{2+}}\] | |
| 7297. |
To an acid solution of an anion a few drops of \[KMn{{O}_{4}}\] solution are added. Which of the following, if present will not decolourise the \[KMn{{O}_{4}}\] solution [MP PMT 1997] |
| A. | \[NO_{2}^{-}\] |
| B. | \[{{S}^{2-}}\] |
| C. | \[C{{l}^{-}}\] |
| D. | \[CO_{3}^{2-}\] |
| Answer» E. | |
| 7298. |
Upon the addition of a solution A to a strongly acidified solution of barium nitrate, a white precipitate was obtained which did not dissolve even after large addition of water. Solution A contained [NCERT 1971] |
| A. | Sodium phosphate |
| B. | Sodium carbonate |
| C. | Sodium sulphate |
| D. | Sodium chloride |
| Answer» D. Sodium chloride | |
| 7299. |
Where chlorine water is added to an aqueous solution of potassium halide in presence of chloroform, a violet colour is obtained. On adding more of chlorine water, the violet colour disappears, and a colourless solution is obtained. This test confirms the presence of the following in aqueous solution [CPMT 1990] |
| A. | Iodide |
| B. | Bromide |
| C. | Chloride |
| D. | Iodide and bromide |
| Answer» B. Bromide | |
| 7300. |
The best explanation for the solubility of MnS in dil. HCl is that [UPSEAT 2001] |
| A. | Solubility product of\[MnC{{l}_{2}}\]is less than that of MnS |
| B. | Concentration of\[M{{n}^{2+}}\]is lowered by the formation of complex ions with chloride ions |
| C. | Concentration of sulphide ions is lowered by oxidation to free sulphur |
| D. | Concentration of sulphide ions is lowered by formation of the weak acid \[{{H}_{2}}S\] |
| Answer» E. | |