List of top Chemistry Questions

Presence of which reagent will affect the reversibility of the following reaction, and change it to a irreversible reaction:
$CH_4 + I_2 \rightleftharpoons CH_3-I + HI$

Consider the above reaction and identify the Product P : 

Match List - I with List - II : 

Choose the most appropriate match : 
 

The compound 'A' is a complementary base of _________ in DNA strands. 

 

The density of NaOH solution is 1.2 g cm$^{-3}$. The molality of this solution is ________ m. (Round off to the Nearest Integer)
[Use : Atomic masses : Na:23.0 u O:16.0 u H:1.0 u, Density of H$_2$O : 1.0 g cm$^{-3}$]
The difference between bond orders of CO and NO$^\oplus$ is $\frac{x}{2}$ where x = _________. (Round off to the Nearest Integer)

For water at 100$^\circ$C and 1 bar, 
(Round off to the Nearest Integer) 
[Use : R=8.31 J mol$^{-1}$ K$^{-1}$] 
[Assume volume of H$\_2$O(l) is much smaller than volume of H$\_2$O(g). Assume H$\_2$O(g) can be treated as an ideal gas] 
 

1.46 g of a biopolymer dissolved in a 100 mL water at 300 K exerted an osmotic pressure of $2.42 \times 10^{-3}$ bar. The molar mass of the biopolymer is _________ $\times 10^4$ g mol$^{-1}$. (Round off to the Nearest Integer)
[Use : R = 0.083 L bar mol$^{-1}$ K$^{-1}$]
$PCl_5 \rightleftharpoons PCl_3 + Cl_2 K_c = 1.844$
3.0 moles of $PCl_5$ is introduced in a 1 L closed reaction vessel at 380 K. The number of moles of $PCl_5$ at equilibrium is _________ $\times 10^{-3}$. (Round off to the Nearest Integer)
The conductivity of a weak acid HA of concentration 0.001 mol L$^{-1}$ is $2.0 \times 10^{-5}$ S cm$^{-1}$. If $\Lambda_m^\circ(HA) = 190$ S cm$^2$ mol$^{-1}$, the ionization constant (K$_a$) of HA is equal to _________ $\times 10^{-6}$. (Round off to the Nearest Integer)
$CO_2$ gas adsorbs on charcoal following Freundlich adsorption isotherm. For a given amount of charcoal, the mass of $CO_2$ adsorbed becomes 64 times when the pressure of $CO_2$ is doubled. The value of n in the Freundlich isotherm equation is _________ $\times 10^{-2}$. (Round off to the Nearest Integer)
The number of geometrical isomers possible in triamminetrinitrocobalt(III) is X and in trioxalatochromate(III) is Y. Then the value of X+Y is _________.
In gaseous triethyl amine the "-C-N-C-" bond angle is _________ degree.
An organic compound is subjected to chlorination to get compound A using 5.0 g of chlorine. When 0.5 g of compound A is reacted with AgNO$_3$ [Carius Method], the percentage of chlorine in compound A is _________ when it forms 0.3849 g of AgCl. (Round off to the Nearest Integer)
(Atomic masses of Ag and Cl are 107.87 and 35.5 respectively)

The plots of radial distribution functions for various orbitals of hydrogen atom against r are given below: The correct plot for 3s orbital is : 

According to molecular orbital theory, the species among the following that does not exist is :
The solubility of AgCN in a buffer solution of pH=3 is x. The value of x is : [Assume : No cyano complex is formed ; $K_{sp}(\text{AgCN}) = 2.2 \times 10^{-16}$ and $K_a(\text{HCN}) = 6.2 \times 10^{-10}$]
In Freundlich adsorption isotherm at moderate pressure, the extent of adsorption $(x/m)$ is directly proportional to $P^x$. The value of x is :
Which of the following equation depicts the oxidizing nature of $H_2O_2$?
The correct statement about B$_2$H$_6$ is :
Given below are two statements : Statement I : CeO$_2$ can be used for oxidation of aldehydes and ketones. Statement II : Aqueous solution of EuSO$_4$ is a strong reducing agent. In the light of the above statements, choose the correct answer :
In which of the following pairs, the outer most electronic configuration will be the same ?
The hybridization and magnetic nature of [Mn(CN)$_6$]$^{4-}$ and [Fe(CN)$_6$]$^{3-}$, respectively are :
Given below are two statements : Statement I : An allotrope of oxygen is an important intermediate in the formation of reducing smog. Statement II : Gases such as oxides of nitrogen and sulphur present in troposphere contribute to the formation of photochemical smog. In the light of the above statements, choose the correct answer from the options given below :

Identify A in the given chemical reaction. CH$_2$=CH-CH(CH$_3$)-CH$_3$ $\xrightarrow{Mo_2O_3, 773 K, 10-20 atm}$ A (major product)