List of top Chemistry Questions

Statement I : Acid strength increases in the order given as HF << HCl << HBr << HI.
 Statement II : As the size of the elements F, Cl, Br, and I increases down the group, the bond strength of HF, HCl, HBr, and HI decreases and so the acid strength increases.
 In light of the above statements, choose the correct answer from the options given below

The molar conductance of NaCl, HCl and CH₃COONa at infinite dilution are 126.45, 426.16 and 91.0 S cm² mol⁻¹ respectively. The molar conductance of CH₃COOH at infinite dilution is. Choose the right option for your answer

The major product of the following chemical reaction is 

Match List - I with List - II.  

Choose the correct answer from the options given below.

Arrange the following in the order of increasing mass (atomic mass $ O=16,Cu=63, $ $ N=14 $ ) I. One atom of oxygen II. One atom of nitrogen III. $1 \times 10^{-10}$ mole of oxygen IV. $1 \times 10^{-10}$ mole of copper

Arrange the following species in the correct order of their stability $C_2 , Li_2, O_2^{+} , He_2^{+}$

For the reaction, A⇌B, E_a = 50kJ mol^-1 and ΔH = -20 kJ mol^-1. When a catalyst is added, E_a decreases by 10kJmol^-1. What is the E_a for the backward reaction in the presence of catalyst?

The number of atoms in 4.5 g of a face-centred cubic crystal with edge length 300 pm is :
(Given density=10gcm^-3 and N_A=6.022×10²³).

In the analysis of III group basic radicals of salts, the purpose of adding NH₄CI_(s), to NH₄OH is:

The energy associated with first orbit is He⁺ is

Which one of the following is a cationic detergent ?

But-1-yne on reaction with dil. \(H_2SO_4\) in presence of \(Hg^{2+}\) ions at 333 K gives :

The correct decreasing order of boiling point of hydrogen halides is

Heating of ore in the absence of air below its melting point is called

Select the correct statement :

The incorrect statement about Hall-Heroult process is :

For the coagulation of positively charged hydrated ferric-oxide sol, the flocculating power of the ions is in the order :

For a first order reaction, $A(g) \rightarrow B(g)$ at $35^{\circ} C$, the volume of $A$ left in reaction vessel at various times are given below. [Given data : $\log (5 / 4)=0.096$. What is the value of rate constant?

Given below are two statements related to Ellingham diagram:
Statement-I: Ellingham diagrams can be constructed for formation of oxides, sulfides and halides of metals. 
Statement-II : It consists of plots of ΔfH° vs T for formation of oxides of elements. 
In the light of the above statements, choose the most appropriate answer from the options given below

Given below are two statements, one is labelled as Assertion: A and the other is labelled as Reason R. 
Assertion: A Isotopes of hydrogen have almost same chemical properties, but difference in their rates of reaction. 
Reason: R Isotopes of hydrogen have different enthalpy of bond dissociation. 
In the light of the above statements, choose the most appropriate answer from the options given below

better method for preparation of bef₂ among the following is

The correct group of halide ions which can be oxidised by oxygen in acidic medium is

Which of the following complexes will exhibit maximum attraction to an applied magnetic field?