datavorous/entrance-exam-dataset huggingface dataset:
Which of the following complexes will show geometrical isomerism?

Options:
A Potassium tris(oxalato)chromate(III)
B Pentaaquachlorochromium(II)chloride
C Aquachlorobis(ethylenediamine)cobalt(II)chloride
D Potassiumamminetrichloroplatinate(II)

The correct answer is:
Aquachlorobis(ethylenediamine)cobalt(II)chloride

Solution:
CoH2OClen2Cl
Potassium tris(oxalato)chromate(III) will show optical isomerism
Aquachlorobis(ethylenediamine)cobalt(II) chloride does not show stereoisomerism
Potassiumamminetrichloroplatinate(II) does not show stereoisomerism.

Topic: Chemistry, Coordination Compounds, JEE Main, JEE Main 2018 (16 Apr Online)
Which of the following compound can form hydrogen bonds

Options:
A $\mathrm{CH}_4$
B $\mathrm{NaCl}$
C $\mathrm{CHCl}_3$
D $\mathrm{H}_2 \mathrm{O}$

The correct answer is:
$\mathrm{H}_2 \mathrm{O}$

Solution:
$\mathrm{H}_2 \mathrm{O}$ can form hydrogen bonds $\mathrm{CH}_4$ and $\mathrm{CHCl}_3$ are organic compound having no oxygen while $\mathrm{NaCl}$ has itself interionic attraction in the molecule.

Topic: Chemistry, Chemical Bonding and Molecular Structure, JEE Main
Which of the following compound can give positive iodoform test when treated with aqueous \(\mathrm{KOH}\) solution followed by potassium hypoiodite.

Options:
A

B

C

D \(\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{CH}_2 \mathrm{CHO}\)

The correct answer is:

Solution:

Topic: Chemistry, Aldehydes and Ketones, JEE Main, JEE Main 2024 (09 Apr Shift 2)
Which of the following compound CANNOT act as a Lewis base?

Options:
A NF3
B PCl5
C SF4
D ClF3

The correct answer is:
PCl5

Solution:
Lewis base: Chemical species which has capability to donate electron pair.

In NF3, SF4, ClF3 central atom (i.e. N,S,Cl)
having lone pair therefore act as Lewis base.

In PCl5, central atom P does not have lone pair therefore does not act as Lewis base.

Topic: Chemistry, Ionic Equilibrium, JEE Main, JEE Main 2021 (17 Mar Shift 1)
Which of the following compound do not undergo enolisation?

Options:
A
B
C
D

The correct answer is:

Solution:
α-H is not available in the compound
So enol form is not possible.

Topic: Chemistry, General Organic Chemistry, JEE Main
Which of the following compound does not contain sulphur atom?

Options:
A Histamine
B Cimetidine
C Saccharin
D Ranitidine

The correct answer is:
Histamine

Solution:
Histamine is nitrogenous compound it does not contain sulpher.

Topic: Chemistry, Chemistry in Everyday Life, JEE Main, JEE Main 2022 (29 Jun Shift 1)
Which of the following compound does not exhibit geometrical Isomerism?

Options:
A 2-Butene
B 3-Hexene
C But-2-enal
D Styrene

The correct answer is:
Styrene

Solution:
Styrene does not exhibit geometrical isomerism as it has three identical groups (H-atoms) on the doubly-bonded carbon atoms.

Topic: Chemistry, General Organic Chemistry, JEE Main
Which of the following compound does not liberate nitrogen with HNO2 ?

Options:
A Carbamide
B Primary amine
C Secondary amine
D Alkanamide

The correct answer is:
Secondary amine

Solution:
R 2 NH + HNO 2 â¶ R 2 N . NO + H 2 O
N-Nitroso Compound

Topic: Chemistry, Amines, JEE Main
Which of the following compound given one mole AgCl precipitate with 100 mL of a 10 M solution of AgNO3 ?

Options:
A CoCl3.6NH3
B CoCl3.5NH3
C CoCl3.4NH3
D All of the above

The correct answer is:
All of the above

Solution:
100 mL of a 10 M solution of AgNO3=1 mole AgNO3

Topic: Chemistry, Coordination Compounds, JEE Main
Which of the following compound gives a ketone with Grignard reagent

Options:
A Formaldehyde
B Ethyl alcohol
C Methyl cyanide
D Methyl iodide

The correct answer is:
Methyl cyanide

Solution:
$\mathrm{CH}_3-\mathrm{CO}-\mathrm{CH}_3+\mathrm{NH}_3+\mathrm{Mg} \quad \begin{array}{cc}\mathrm{Or} \\ \end{array}$

Topic: Chemistry, Aldehydes and Ketones, JEE Main
Which of the following compound gives a ketone with Grignard reagent

Options:
A Formaldehyde
B Ethyl alcohol
C Methyl cyanide
D Methyl iodide

The correct answer is:
Methyl cyanide

Solution:

Topic: Chemistry, Aldehydes and Ketones, JEE Main
Which of the following compound gives red colour with ceric ammonium nitrate

Options:
A
B
C
D

The correct answer is:

Solution:
alcohols give red colour with ceric ammonium nitrate.

Topic: Chemistry, Alcohols Phenols and Ethers, JEE Main
Which of the following compound is added to the sodium extract before addition of silver nitrate for testing of halogens?

Options:
A Nitric acid
B Sodium hydroxide
C Ammonia
D Hydrochloric acid

The correct answer is:
Nitric acid

Solution:
For testing of halogens, Nitric acid is added to the sodium extract because if CN- or S2- are present then they will be oxidised and removed before the test of halides.

NaCN+HNO3→NaNO3+HCN↑
Na2S+HNO3→NaNO3+H2S↑
Nilnic acid decomposed NaCN & Na2S, else they precipitate in test & misquite the resolve

Topic: Chemistry, General Organic Chemistry, JEE Main, JEE Main 2021 (25 Feb Shift 2)
Which of the following compound is most basic?

Options:
A

B

C

D

The correct answer is:

Solution:
Compound is most basic due to localised lone pair of electrons on nitrogen atom while in other compounds, as a result of resonance, the lone pair of electrons on nitrogen atom gets delocalised over benzene ring and thus is less easily available for donation.

Topic: Chemistry, General Organic Chemistry, JEE Main
Which of the following compound is most basic?

Options:
A

B

C

D

The correct answer is:

Solution:
Compound is most basic due to localised lone pair of electrons on nitrogen atom while in other compounds, as a result of resonance, the lone pair of electrons on nitrogen atom gets delocalised over benzene ring and thus is less easily available for donation.

Topic: Chemistry, General Organic Chemistry, NEET, NEET 2011 (Mains)
Which of the following compound is not a Aromatic aldehyde?

Options:
A
B
C
D

The correct answer is:

Solution:
Aromatic aldehydes are the one's with -CHO group with benzene ring

Topic: Chemistry, General Organic Chemistry, JEE Main
Which of the following compound is not aromatic?

Options:
A 1,3 -cyclobutene
B Pyridine
C Furane
D Thiophene

The correct answer is:
1,3 -cyclobutene

Solution:
Aromatic compounds satisfy $(4 n+2) \pi$ Huckel rule.
(a) 1,3 -cyclobutene
Number of $\pi$ electrons $=4$
$\because$ It is not equal to $4 n+2$
$\therefore$ It is not an aromatic compound
(b) Pyridine
Number of $\pi$ electrons $=6(=4 n+2)$ (Here lone pair of electrons of N does not evolve in delocalisation)
(c) Furane
Number of $\pi$ electrons $=4+2=6(=4 n+2)$
(d) Thiophene
Number of $\pi$ electrons $=6(=4 n+2)$
Thus, except 1,3 -cyclobutene, all species are aromatic in nature.

Topic: Chemistry, General Organic Chemistry, JEE Main
Which of the following compound is not chiral?

Options:
A
1- chloropentane

B
3-chloro-2- methyl pentane

C
1-chloro -2- methyl pentane

D
2- chloropentane

The correct answer is:
1- chloropentane

Solution:

Topic: Chemistry, General Organic Chemistry, JEE Main, JEE Main 2004
Which of the following compound is not formed in haloform reaction?

Options:
A CHF3
B CHCl3
C CHI3
D CHBr3

The correct answer is:
CHF3

Solution:
CHF 3 is not formed because the formation of CHF 3 is a highly exothermic reaction.

Topic: Chemistry, Carboxylic Acid Derivatives, JEE Main
Which of the following compound is obtained by heating ammonium cyanate?

Options:
A Alkane
B Urea
C Ethylamine
D Ammonium thiocyanate

The correct answer is:
Urea

Solution:
Urea is obtained by heating ammonium cyanate
$$
\mathrm{NH}_{4} \mathrm{CNO} \stackrel{\Delta}{\longrightarrow} \mathrm{NH}_{2} \mathrm{CONH}_{2}
$$
Ammonium cyanate Urea

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), JEE Main
Which of the following compound is the most basic?

Options:
A
B
C
D

The correct answer is:

Solution:
is most basic among the following because of more pronounced +R effect of -O¨-CH3 group.

* Basic strength α EDG.

Topic: Chemistry, General Organic Chemistry, JEE Main
Which of the following compound is unsaturated hydrocarbon?

Options:
A

B $\mathrm{CH}_3-\mathrm{C}=\mathrm{N}$
C

D

The correct answer is:

Solution:
According to IUPAC only alkene and alkyne are unsaturated hydrocarbon.

Topic: Chemistry, General Organic Chemistry, JEE Main
Which of the following compound of xenon does not exists?

Options:
A XeF $_{6}$
B $\mathrm{XeF}_{4}$
C $\mathrm{XeF}_{5}$
D $\mathrm{XeF}_{2}$

The correct answer is:
$\mathrm{XeF}_{5}$

Solution:
Xenon forms following fluorides
$\mathrm{XeF}_{2}, \mathrm{XeF}_{4}$ and $\mathrm{XeF}_{6}$
It does not exists as $\mathrm{XeF}_{5}$.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), JEE Main
Which of the following compound will give positive iodoform test?

Options:
A Isopropyl alcohol
B Propionaldehyde
C Ethylphenyl ketone
D Benzyl alcohol

The correct answer is:
Isopropyl alcohol

Solution:
Alcohols having Structure give positive iodoform test.

Topic: Chemistry, Aldehydes and Ketones, JEE Main
Which of the following compound will make precipitate most readily with $\mathrm{AgNO}_3$

Options:
A $\mathrm{CCl}_3 \mathrm{CHO}$
B $\mathrm{CHCl}_3$
C $\mathrm{C}_6 \mathrm{H}_5 \mathrm{CH}_2 \mathrm{Cl}$
D $\mathrm{CHI}_3$

The correct answer is:
$\mathrm{CHI}_3$

Solution:
$\mathrm{CHI}_3$ gives a yellow ppt. of $\mathrm{Agl}$.

Topic: Chemistry, Haloalkanes and Haloarenes, JEE Main
Which of the following compound will most easily be attacked by an electrophile?

Options:
A
B
C
D

The correct answer is:

Solution:
Ortho, para directing groups are electron-donating groups; meta directing groups are electron-withdrawing groups. The halide ions, which are electron-withdrawing but ortho, para directing, are the exception.

Here -OH group is strong electron donating group. Hence electrophile can easily give electron.

-OH group in phenol can release electrons to the ring better than -CH3 group in toluene. Cl atom has electron withdrawing effect which inhibits electrophile attack readily.

Topic: Chemistry, Hydrocarbons, JEE Main, JEE Main 2024 (01 Feb Shift 1)
Which of the following compound will not undergo amine inversion?

Options:
A
B CH3-NH-CH3
C NH3
D

The correct answer is:

Solution:
In flipping is restricted due to rigidity of the ring system.

Topic: Chemistry, Amines, JEE Main
Which of the following compound will undergo tautomerism?

Options:
A
B
C
D

The correct answer is:

Solution:
This compound has α -H on saturated carbon atom so it can show tautomerism.

Topic: Chemistry, General Organic Chemistry, JEE Main
Which of the following compounds are antiaromatic

Options:
A
(I) and (V)

B
(II) and (V)

C
(I) and (IV)

D
(V) and (VI)

The correct answer is:
(V) and (VI)

Solution:
For a compound to be aromatic it must have $(4 n+2) \pi e^{-}$and system should be planar where $n$ is an integer. (V) and (VI) both have $4 e^{-}$and planar structure. Hence are Antiaromatic

Topic: Chemistry, General Organic Chemistry, JEE Main, JEE Main 2012 (26 May Online)
Which of the following compounds are not used as disinfectants?

A. Chloroxylenol
B. Bithional
C. Veronal
D. Prontosil
E. Terpineol

Choose the correct answer from the options given below:

Options:
A A, B, E
B C, D
C A, B
D B, D, E

The correct answer is:
C, D

Solution:
Antiseptics and disinfectants are also chemicals that either kill or prevent the growth of microorganisms. Antiseptics are applied to living tissues such as wounds, cuts, ulcers and diseased skin surfaces. Examples are furacine, soframicine, etc. Commonly used antiseptic, Dettol is a mixture of chloroxylenol and terpineol. Bithionol (the compound is also called bithional) is added to soaps to impart antiseptic properties. Protonsil is an antibiotic, whereas veronal is a tranquilizer which is used for the treatment of stress and mild or severe mental diseases.

So, Veronal and Prontosil are not used as disinfectant.

Topic: Chemistry, Chemistry in Everyday Life, JEE Main, JEE Main 2023 (31 Jan Shift 2)
Which of the following compounds can be detected by Molisch's test ?

Options:
A
Nitro compounds

B
Sugars

C
Amines

D
Primary alcohols

The correct answer is:
Sugars

Solution:
Molisch's Test : when a drop or two of alcoholic solution of $\alpha$-naphthol is added to sugar solution and then conc. $\mathrm{H}_2 \mathrm{SO}_4$ is added along the sides of test tube, formation of violet ring takes place at the junction of two liquids.

Topic: Chemistry, Aldehydes and Ketones, JEE Main
Which of the following compounds can be detected by Molisch's test ?

Options:
A
Nitro compounds

B
Sugars

C
Amines

D
Primary alcohols

The correct answer is:
Sugars

Solution:
Molisch's Test : when a drop or two of alcoholic solution of $\alpha$-naphthol is added to sugar solution and then conc. $\mathrm{H}_2 \mathrm{SO}_4$ is added along the sides of test tube, formation of violet ring takes place at the junction of two liquids.

Topic: Chemistry, Aldehydes and Ketones, JEE Main, JEE Main 2012 (Offline)
Which of the following compounds can be prepared in good yield by Gabriel phthalimide synthesis ?

Options:
A
B CH3−CH2−NHCH3
C
D

The correct answer is:

Solution:

Topic: Chemistry, Amines, JEE Main, JEE Main 2020 (06 Sep Shift 2)
Which of the following compounds can be used as antifreeze in automobile radiators?

Options:
A Methyl alcohol
B Glycol
C Nitrophenol
D Ethyl alcohol

The correct answer is:
Glycol

Solution:
Glycol is widely used as an antifreeze in automobile radiators.

Topic: Chemistry, Solutions, NEET, NEET 2012 (Mains)
Which of the following compounds cannot be prepared singly by the Wurtz reaction?

Options:
A $\mathrm{C}_{2} \mathrm{H}_{6}$
B $\left(\mathrm{CH}_{3}\right)_{2} \mathrm{CHCH}_{3}$
C $\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{CH}_{3}$
D All of the above can be prepared

The correct answer is:
$\left(\mathrm{CH}_{3}\right)_{2} \mathrm{CHCH}_{3}$

Solution:
If two different alkyl halides $\left(\mathrm{R}_{1}-\mathrm{X}\right.$ and $\left.\mathrm{R}_{2}-\mathrm{X}\right)$ are used, a mixture of three alkanes is obtained which is difficult to separate.

Topic: Chemistry, Hydrocarbons, JEE Main
Which of the following compounds contain(s) no covalent bond(s)?
KCl, PH3, O2, B2H6, H2SO4

Options:
A KCl, B2H6
B KCl, B2H6, PH3
C KCl, H2SO4
D KCl

The correct answer is:
KCl

Solution:
PH3O2B2H6H2SO4 All are covalent compounds
KCl is an ionic compound.

Topic: Chemistry, Chemical Bonding and Molecular Structure, JEE Main, JEE Main 2018 (08 Apr)
Which of the following compounds contains no covalent bond(s)?
NaCl,PH3,O2,B2H6,H2SO4,CaCl2

Options:
A NaCl,B2H6
B NaCl,B2H6,PH3
C NaCl,H2SO4
D NaCl ,CaCl2

The correct answer is:
NaCl ,CaCl2

Solution:
NaCl and CaCl2 contains only ionic bond between Na+ and Cl- ions Na+Cl- and between Ca2+ and Cl- respectively while rest other compounds have covalent bonds as follows

Topic: Chemistry, Chemical Bonding and Molecular Structure, JEE Main
Which of the following compounds corresponds Van't Hoff factor ' $i$ ' to be equal to 2 for dilute solution

Options:
A $\mathrm{K}_2 \mathrm{SO}_4$
B $\mathrm{NaHSO}_4$
C Sugar
D $\mathrm{MgSO}_4$

The correct answer is:
$\mathrm{MgSO}_4$

Solution:
$\mathrm{MgSO}_4$ dissociates to give 2 ions.

Topic: Chemistry, Solutions, JEE Main
Which of the following compounds display geometrical isomerism?

Options:
A H 2 C = CHBr
B H 2 C =  CBr 2
C (Cl)HCâ=âCH(Br)
D Br 2 C= CCl 2

The correct answer is:
(Cl)HC = CH(Br)

Solution:
Each end of double bond must contain different atoms (or) groups to show geometrical isomerism.

Topic: Chemistry, General Organic Chemistry, JEE Main
Which of the following compounds does not exhibit resonance ?

Options:
A CH3CH2OCH=CH2
B
C CH3CH2CH2CONH2
D CH3CH2CH=CHCH2NH2

The correct answer is:
CH3CH2CH=CHCH2NH2

Solution:
CH3-CH2-CH=CH-CH2-NH2
No conjugation thus resonance is not possible.

Topic: Chemistry, General Organic Chemistry, JEE Main, JEE Main 2021 (22 Jul Shift 1)
Which of the following compounds does not give nitrogen on heating?

Options:
A NaN 3
B NH42SO4
C NH4NO2
D NH42Cr2O7

The correct answer is:
NH42SO4

Solution:
(i) 2NaN3→2Na+3N2 ;
(ii) NH42SO4→2NH3+H2SO4 ;
(iii) NH4NO2→N2+2H2O .
(iv) NH42Cr2O7→ΔN2+Cr2O3+4H2O .

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), JEE Main
Which of the following compounds does not have any geometrical isomer?

Options:
A
B
C
D

The correct answer is:

Solution:
â Only one carbon of the ring consist pair of different groups
â Thus, it doesn't show geometrical Isomerism.

Topic: Chemistry, General Organic Chemistry, JEE Main
Which of the following compounds exhibits linkage isomerism

Options:
A $\left[\mathrm{Co}(e n)_3\right] \mathrm{Cl}_3$
B $\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_6\left[\mathrm{Cr}(\mathrm{CN})_6\right]\right.$
C $\left[\mathrm{Co}(e n)_2 \mathrm{NO}_2 \mathrm{Cl}\right] \mathrm{Br}$
D $\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_5 \mathrm{Cl}\right] \mathrm{Br}_2$

The correct answer is:
$\left[\mathrm{Co}(e n)_2 \mathrm{NO}_2 \mathrm{Cl}\right] \mathrm{Br}$

Solution:
$\left[\mathrm{Co}(e n)_2 \mathrm{NO}_2 \mathrm{Cl}\right] \mathrm{Br}$ will exhibit linkage isomerism as it contains nitrite ligand which have the same composition differing with the connectivity of the metal to a ligand.It can bind from \(\mathrm{N}\) as well as from \(\mathrm{O}\) side.

Topic: Chemistry, Coordination Compounds, JEE Main
Which of the following compounds gives trichloromethane on distilling with bleaching powder?

Options:
A Ethanol
B Methanol
C Methanal
D Phenol

The correct answer is:
Ethanol

Solution:
Ethanol gives trichloromethane on distilling with bleaching powder.
$\begin{aligned}
&\text { (I) } \mathrm{Cl}_{2}+\mathrm{H}_{2} \mathrm{O} \longrightarrow 2 \mathrm{HCl}+[\mathrm{O}] \\
&\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OH}+[\mathrm{O}] \longrightarrow \mathrm{CH}_{3} \mathrm{CHO}+\mathrm{H}_{2} \mathrm{O}
\end{aligned}$
Ethanol
(II) $\mathrm{CH}_{3} \mathrm{CHO}+3 \mathrm{Cl}_{2} \longrightarrow \mathrm{CCl}_{3} \mathrm{CHO}+3 \mathrm{HCl}$
(III) $\mathrm{CCl}_{3} \mathrm{CHO}+\mathrm{Ca}(\mathrm{OH})_{2} \longrightarrow$
$2 \mathrm{CHCl}_{3}+(\mathrm{HCOO})_{2} \mathrm{Ca}$
Trichloro methane

Topic: Chemistry, Haloalkanes and Haloarenes, JEE Main
Which of the following compounds has a P-P Bond?

Options:
A HPO33
B H4P2O6
C H4P2O7
D H4P2O5

The correct answer is:
H4P2O6

Solution:
Hypo phosphoric acid (H4P2O6) with P in (+IV) oxidation state and one O atom less than pyro phosphoric acid.

H4P2O6

H4P2O7

Pyrophosphorous acid H4P2O5

\

H3PO33Metaphosphoric acid

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), JEE Main
Which of the following compounds has a P-P Bond?

Options:
A HPO33
B H4P2O6
C H4P2O7
D H4P2O5

The correct answer is:
H4P2O6

Solution:
Hypo phosphoric acid (H4P2O6) with P in (+IV) oxidation state and one O atom less than pyro phosphoric acid.

H4P2O6

H4P2O7

Pyrophosphorous acid H4P2O5

\

H3PO33Metaphosphoric acid

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), JEE Main, JEE Main 2015 (11 Apr Online)
Which of the following compounds has peroxide linkage

Options:
A $\mathrm{Pb}_2 \mathrm{O}_3$
B $\mathrm{SiO}_2$
C $\mathrm{CO}_2$
D $\mathrm{PbO}_2$

The correct answer is:
$\mathrm{PbO}_2$

Solution:
In $\mathrm{H}_2 \mathrm{O}, \mathrm{SiO}_2, \mathrm{CO}_2$ and $\mathrm{PbO}_2$, oxidation states of oxygen are $-2,-2,-2 \&-1$ respectively. Oxidation state of oxygen in peroxide linkage is -1 . Hence, Option "4" is the correct answer.

Topic: Chemistry, p Block Elements (Group 13 & 14), JEE Main
Which of the following compounds has wrong IUPAC name ?

Options:
A

B

C

D

The correct answer is:

Solution:
No Solution Available

Topic: Chemistry, General Organic Chemistry, JEE Main, JEE Main 2002
Which of the following compound(s) has ' $Z$ ' configuration?

Options:
A (i) only
B (ii) only
C (iii) only
D (i) and (iii)

The correct answer is:
(i) and (iii)

Solution:
When the groups with higher priority (ie, with high atomic number) are present on same side of double bond, then the configuration is $Z$ but when present on opposite side of double bond, the configuration is $E$.
(Priority : $\mathrm{Br}>\mathrm{Cl}$ and $\mathrm{CH}_3>\mathrm{H}$ )
Hence, compound (i) and (iii) have $(Z)$ configuration.

Topic: Chemistry, General Organic Chemistry, JEE Main
Which of the following compounds have magnetic moment identical with $\left[\mathrm{Cr}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}$

Options:
A $\left[\mathrm{Cu}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+}$
B $\left[\mathrm{Mn}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}$
C $\left[\mathrm{Fe}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}$
D $\left[\mathrm{Mn}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{4+}$

The correct answer is:
$\left[\mathrm{Mn}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{4+}$

Solution:
$\left[\mathrm{Cr}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}$
$\mathrm{Cr} \Rightarrow(\mathrm{Ar}) 3 \mathrm{~d}^{5} 4 \mathrm{~s}^{1}$
$\mathrm{Cr}^{+3} \Rightarrow(\mathrm{Ar}) 3 \mathrm{~d}^{3} 4 \mathrm{~s}^{0}$

Topic: Chemistry, Coordination Compounds, JEE Main
Which of the following compounds have the same value of van't Hoff s factor $(i)$ as that of $\mathrm{Al}_{2}\left(\mathrm{SO}_{4}\right)_{3}$ ?

Options:
A $\mathrm{K}_{4}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]$
B $\mathrm{NaCl}$
C $\mathrm{Al}\left(\mathrm{NO}_{3}\right)_{3}$
D $\mathrm{Na}_{2} \mathrm{SO}_{4}$

The correct answer is:
$\mathrm{K}_{4}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]$

Solution:
The dissociation of compounds take place as follows:
$\mathrm{Al}_{2}\left(\mathrm{SO}_{4}\right)_{3} \longrightarrow 2 \mathrm{Al}^{3+}+3 \mathrm{SO}_{4}^{2-}, i=5$
$\mathrm{~K}_{4}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right] \longrightarrow 4 \mathrm{~K}^{+}+\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4-}, i=5$
$\mathrm{NaCl} \longrightarrow \mathrm{Na}^{+}+\mathrm{Cl}^{-}, i=2$
$\mathrm{Al}\left(\mathrm{NO}_{3}\right)_{3} \longrightarrow \mathrm{Al}^{3+}+3 \mathrm{NO}_{3}^{-}, i=4$
$\mathrm{Na}_{2} \mathrm{SO}_{4} \longrightarrow 2 \mathrm{Na}^{+}+\mathrm{SO}_{4}^{2-}, i=3$

Topic: Chemistry, Solutions, JEE Main
Which of the following compounds is a constituent of the polymer

Options:
A Methylamine
B Ammonia
C Formaldehyde
D N-Methyl urea

The correct answer is:
Formaldehyde

Solution:
Polymer given here is Urea-formaldehyde resin and monomer of this compounds are urea and formaldehyde.

Topic: Chemistry, Polymers, JEE Main, JEE Main 2019 (09 Apr Shift 2)
Which of the following compounds is an example of Freon?

Options:
A C2H2 F2
B C2 F4
C C2HF3
D C2Cl2 F2

The correct answer is:
C2Cl2 F2

Solution:
C2Cl2​F2â is an example of freon. It can act as an aerosol propellant, refrigerant, or organic solvent because it is a gas at room temperature and a liquid when cooled or compressed. Freon is a term that was commonly used to refer to a group of chlorofluorocarbon (CFC) and hydrochlorofluorocarbon (HCFC) compounds.

Topic: Chemistry, Environmental Chemistry, JEE Main, JEE Main 2023 (11 Apr Shift 2)
Which of the following compounds is an example of hypnotic drug?

Options:
A Seldane
B Amytal
C Aspartame
D Prontosil

The correct answer is:
Amytal

Solution:
Derivatives of barbituric acid viz., veronal, amytal, nembutal, luminal and seconal constitute an important class of tranquilizers. These derivatives are called barbiturates. Barbiturates are hypnotic. i.e., sleep producing agents.

Amytal is hypnotic drug used to treat sleep disorder.

Topic: Chemistry, Chemistry in Everyday Life, JEE Main, JEE Main 2022 (29 Jul Shift 1)
Which of the following compounds is brown coloured

Options:
A $\mathrm{Fe}\left[\mathrm{Fe}(\mathrm{CN})_4\right]$
B $\mathrm{Fe}\left[\mathrm{Fe}(\mathrm{CN})_6\right]$
C $\mathrm{Fe}_4\left[\mathrm{Fe}(\mathrm{CN})_6\right]$
D $\mathrm{K}_2 \mathrm{Fe}\left[\mathrm{Fe}(\mathrm{CN})_6\right]$

The correct answer is:
$\mathrm{Fe}\left[\mathrm{Fe}(\mathrm{CN})_6\right]$

Solution:
$\mathrm{Fe}\left[\mathrm{fe}(\mathrm{CN})_6\right]$ has $\mathrm{Fe}$ in +3 oxidation state and is brown colours.

Topic: Chemistry, Practical Chemistry, JEE Main