List of top Chemistry Questions

The Novolac polymer has mass of 963 g. The number of monomer units present in it are
How many of the given compounds will give a positive Biuret test_________? Glycine, Glycylalanine, Tripeptide, Biuret.
The neutralization occurs when 10 mL of 0.1M acid ‘A’ is allowed to react with 30 mL of 0.05 M base M(OH)2. The basicity of the acid ‘A’ is____[M is a metal]
Which of the following compounds is an example of hypnotic drug?

Match List-I with List-II :
 

List-IList-II
(A) Negatively charged sol(I) Fe2O3.xH2O
(B) Macromolecular colloid(II) CdS sol
(C) Positively charged sol(III) Starch
(D) Cheese(IV) a gel


Choose the correct answer from the options given below:

Which of the following oxoacids of sulphur contains \(S\) in two different oxidation states?

With respect to the following reaction, consider the given statements:

Fig








(A) o-Nitroaniline and p-nitroaniline are the predominant products.
(B) p-Nitroaniline and m-nitroaniline are the predominant products.
(C) HNO3 acts as an acid.
(D) H2SO4 acts as an acid.
Choose the correct option.

Consider the above reaction, the compound ‘A’ is :

Fig.
In neutral or faintly alkaline medium, KMnO4 being a powerful oxidant can oxidize, thiosulphate almost quantitatively, to sulphate. In this reaction overall change in oxidation state of manganese will be
Consider the reaction
\(4\text{HNO}_3(\text{l}) + 3\text{KCl}(\text{s}) \rightarrow \text{Cl}_2(\text{g}) + \text{NOCl}(\text{g}) + 2\text{H}_2\text{O}(\text{g}) + 3\text{KNO}_3(\text{s})\)
The amount of HNO3 required to produce 110.0 g of KNO3 is
(Given : Atomic masses of H, O, N and K are 1, 16, 14 and 39 respectively.)
Which statement is not true with respect to nitrate ion test?
Statement-I: An alloy of lithium and magnesium is used to make aircraft plates. 
Statement-II: The magnesium ions are important for cell-membrane integrity. 
In the light of the above statements, choose the correct answer from the options given below:
Given below are two statements: one is labelled as Assertion A and other is labelled as Reason R.
Assertion A : Finest gold is red in colour, as the size of the particles increases, it appears purple then blue and finally gold.
Reason R : The colour of the colloidal solution depends on the wavelength of light scattered by the dispersed particles.
In the light of the above statements, choose the most appropriate answer from the options given below.
0.2 g of an organic compound was subjected to estimation of nitrogen by Duma’s method in which volume of N2 evolved (at STP) was found to be 22.400 mL. The percentage of nitrogen in the compound is _____. [nearest integer] 
(Given : Molar mass of N2 is 28 g mol–1, Molar volume of N2 at STP : 22.4L)
Fig. Reaction

Consider the above reaction. The number of π electrons present in the product ‘P’ is _____ .

In alanylglycylleucylalanyvaline, the number of peptide linkages is__,
At 300 K, a sample of 3.0 g of gas A occupies the same volume as 0.2 g of hydrogen at 200 K at the same pressure. The molar mass of gas A is _____ g mol–1. (nearest integer)
Assume that the behaviour of gases as ideal.
(Given: The molar mass of hydrogen (H2) gas is 2.0 g mol–1).
A company dissolves \(‘X’\) amount of \(CO_2\) at \(298\ K\) in \(1\) litre of water to prepare soda water. \(X\) = _____ \(× 10^{–3}\) g. (nearest integer)
(Given: partial pressure of \(CO_2\) at \(298\ K = 0.835\) bar. Henry’s law constant for \(CO_2\) at \(298\ K = 1.67\) Kbar. Atomic mass of \(H\), \(C\) and \(O\) is \(1\), \(12\), and \(6\) g mol–1, respectively)
\(PCl_5\) dissociates as
\(PCl_5(g) ⇌ PCl_3(g)+ Cl_2(g)\)
\(5\) moles of \(PCl_5\) are placed in a \(200\) litre vessel which contains \(2\) moles of \(N_2\) and is maintained at \(600\ K\). The equilibrium pressure is \(2.46\) atm. The equilibrium constant Kp for the dissociation of \(PCl_5\) is ______ \(× 10^{–3}\). (nearest integer) 
(Given: \(R = 0.082\) L atm K–1 mol–1; Assume ideal gas behaviour)
The resistance of a conductivity cell containing \(0.01\) M KCl solution at \(298\ K\) is \(1750\ Ω\). If the conductivity of \(0.01\) M KCl solution at \(298\ K\) is \(0.152×10^{–3}\) S cm–1, then the cell constant of the conductivity cell is ______ \(×10^{–3}\) cm–1.
When 200 mL of 0.2 M acetic acid is shaken with 0.6 g of wood charcoal, the final concentration of acetic acid after adsorption is 0.1 M. The mass of acetic acid adsorbed per gram of carbon is _____ g.
(a) Baryte,
(b) Galena, 
(c) Zinc blende and 
(d) Copper pyrites. 
How many of these minerals are sulphide based?
Manganese (VI) has ability to disproportionate in acidic solution. The difference in oxidation states of two ions it forms in acidic solution is _____.
While estimating the nitrogen present in an organic compound by Kjeldahl’s method, the ammonia evolved from 0.25g of the compound neutralized 2.5mL of 2M H2SO4. The percentage of nitrogen present in organic compound is ________
A 2.0 g sample containing MnO2 is treated with HCl liberating Cl2. The Cl2 gas is passed into a solution of KI and 60.0 mL of 0.1 M Na2S2O3 is required to titrate the liberated iodine. The percentage of MnO2 in the sample is ______. (Nearest integer)
[Atomic masses (in u) Mn = 55; Cl = 35.5; O = 16, I = 127, Na = 23, K = 39, S = 32]