List of top Chemistry Questions

The correct structures of trans-[NiBr₂(PPh₃)₂] and meridional-[Co(NH₃)₃(NO₂)₃], respectively, are : 

Staggered and eclipsed conformers of ethane are :

Consider the above reaction and identify the Product P : 

In the following molecule,

Hybridisation of Carbon a, b and c respectively are :

The transformation occurring in Duma's method is given below:
$\text{C}_2 \text{H}_7 \text{N} + (2x + y/2) \text{CuO} \to x \text{CO}_2 + y/2 \text{H}_2\text{O} + z/2 \text{N}_2 + (2x + y/2) \text{Cu}$.
The value of $y$ is ________. (Integer answer)

What is the final product (major) 'A' in the given reaction ? $CH_3 - CH = CH - CH_3 \xrightarrow{HCl} A$ 

Which one of the following reactions will not form acetaldehyde ?
Presence of which reagent will affect the reversibility of the following reaction, and change it to a irreversible reaction:
$CH_4 + I_2 \rightleftharpoons CH_3-I + HI$

Which one of the following compounds will give orange precipitate when treated with 2,4-dinitrophenyl hydrazine ? 

Consider the above reaction, the major product "P" formed is : 

 

Consider the reaction: CH$\equiv$CH $\xrightarrow{\text{Red hot Fe}}$ (1) $\xrightarrow{CO, HCl, AlCl_3}$ (2). The number of sp$^2$ hybridized carbon atom(s) in the product is __________.

The correct order of stability of given carbocations is : 

The correct sequence of reagents used in the preparation of 4-bromo-2-nitroethylbenzene from benzene is:
Match List - I and List - II. List - I : (a) R-COCl $\to$ R-CHO (b) R-CH2-COOH $\to$ R-CH-Cl-COOH (c) R-CONH2 $\to$ R-NH2 (d) R-COCH3 $\to$ R-CH2-CH3 List - II : (i) Br2/NaOH (ii) H2/Pd-BaSO4 (iii) Zn(Hg)/Conc. HCl (iv) Cl2/Red P, H2O
Which one of the following set of elements can be detected using sodium fusion extract ?
Given below are two statements :
Statement I : Hyperconjugation is a permanent effect.
Statement II : Hyperconjugation in ethyl cation \( (\mathrm{CH_3-CH_2^+}) \) involves the overlapping of \( \mathrm{C_{sp^2}-H_{1s}} \) bond with empty \( 2p \) orbital of the other carbon.
Choose the correct option :
Match List - I with List - II : List - I
(a) Chlorophyll
(b) Vitamin - B₁₂
(c) Anticancer drug
(d) Grubbs catalyst List - II
(i) Ruthenium
(ii) Platinum
(iii) Cobalt
(iv) Magnesium
Match List - I with List - II : List - I (Chemicals)
(a) Alcoholic potassium hydroxide
(b) Pd/BaSO₄
(c) BHC (Benzene hexachloride)
(d) Polyacetylene List - II (Use/Preparation/Constituent)
(i) electrodes in batteries
(ii) obtained by addition reaction
(iii) used for β-elimination reaction
(iv) Lindlar's Catalyst
The solubility product of PbI2 is \( 8.0 \times 10^{-9} \). The solubility of lead iodide in 0.1 molar solution of lead nitrate is \( x \times 10^{-6} \) mol/L. The value of \( x \) is __________. (Rounded off to the nearest integer) [Given \( \sqrt{2} = 1.41 \)]
The volume occupied by 4.75 g of acetylene gas at 50 °C and 740 mmHg pressure is _______ L. (Rounded off to the nearest integer) [Given \( R = 0.0826 \, \text{L atm K}^{-1} \text{ mol}^{-1} \)]

Which of the following reagent is suitable for the preparation of the product in the above reaction ? (reaction of ketone to alkane)

The correct order of the following compounds showing increasing tendency towards nucleophilic substitution reaction is : (Note: The compounds are chloro benzene with different nitro positions: (i) Chlorobenzene, (ii) 4-nitrochlorobenzene, (iii) 2,4-dinitrochlorobenzene, (iv) 2,4,6-trinitrochlorobenzene)

Match List - I with List - II. 

Match List - I with List - II. 

Among the following allotropic forms of sulphur, the number of allotropic forms, which will show paramagnetism is __________