List of top Chemistry Questions

The reaction of zinc with excess of aqueous alkali, evolves hydrogen gas and gives:
Lithium nitrate and sodium nitrate, when heated separately, respectively, give :
A 1.84 mg sample of polyhydric alcoholic compound ‘X’ of molar mass 92.0 g/mol gave 1.344 mL of H2 gas at STP. The number of alcoholic hydrogens present in compound ‘X’ is____.
In following pairs, the one in which both transition metal ions are colourless is :
For a cell, \(Cu(s)|Cu^{2+}(0.001M)||Ag^+(0.01M)|Ag(s)\)
the cell potential is found to be \(0.43 V\) at \(298 K\). The magnitude of standard electrode potential for \(Cu^{2+}/{Cu}\) is ____ \(× 10^{–2}\) V.
[Given: \(E_{Ag^+/Ag^⊖}=0.80\) V and \(\frac {2.303RT}{F}=0.06 V\)]
The number of stereoisomers formed in a reaction of (±) Ph (C = O) C (OH) (CN) Ph with HCN is_____.
[Where, Ph is – C6H5]
Sum of oxidation state (magnitude) and coordination number of cobalt in \(Na[Co(bpy)Cl_4]\) is____ .
(Given : bpy =Sum of oxidation state (magnitude) and coordination number of cobalt)
Fig,

Consider the above reaction sequence, the product ‘C’ is

The number of chlorine atoms in bithionol is ______ .

A compound ‘X’ is acidic and it is soluble in NaOH solution, but insoluble in NaHCO3 solution. Compound ‘X’ also gives violet colour with neutral FeCl3 solution. The compound ‘X’ is :
 

Assuming 1μg of trace radioactive element X with a half life of 30 years is absorbed by a growing tree. The amount of X remaining in the tree after 100 years is ______ × 10–1μg.
[Given : ln 10 = 2.303; log 2 = 0.30]
Correct structure of γ-methylcyclohexane carbaldehyde is
A compound ‘X’ is a weak acid and it exhibits colour change at pH close to the equivalence point during neutralization of NaOH with CH3COOH. Compound ‘X’ exists in ionized from in basic medium. The compound ‘X’ is
Given below are two statements. One is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : Amylose is insoluble in water.
Reason R : Amylose is a long linear molecule with more than 200 glucose units.
In the light of the above statements, choose the correct answer from the options given below.
Which of the following is not a natural polymer?
Compound ‘A’ undergoes following sequence of reactions to give compound ‘B’. The correct structure and chirality of compound ‘B’ is
[where Et is –C2H5]
sequence of reactions to give compound
Given below are two statements.
Statement-I: Stannane is an example of a molecular hydride.
Statement-II: Stannane is a planar molecule
In the light of the above statement, choose the most appropriate answer from the options given below.
In liquation process used for tin (Sn), the metal
When ethanol is heated with conc. H2SO4, a gas is produced. The compound formed, when this gas is treated with cold dilute aqueous solution of Baeyer’s reagent, is
Portland cement contains ‘X’ to enhance the setting time. What is ‘X’?
Which of the following compounds is an example of hypnotic drug?
Which of the following 3d-metal ion will give the lowest enthalpy of hydration (ΔhydH) when dissolved in water?

Given below are the quantum numbers for 4 electrons.
A. n=3, l=2, ml=1,ms=+\(\frac{1}{2}\)
B. n=4, l=1, ml=0,ms=+\(\frac{1}{2}\)
C. n=4, l=2, ml=–2,ms=–\(\frac{1}{2}\)
D. n=3, l=1, ml=–1,ms=+\(\frac{1}{2}\)
The correct order of increasing energy is

C(s)+O2(g)→CO2(g)+400 kJ
C(s)+\(\frac{1}{2}\) O2(g)→CO(s)+100 kJ
When coal of purity 60% is allowed to burn in presence of insufficient oxygen, 60% of carbon is converted into ‘CO’ and the remaining is converted into ‘CO2’. The heat generated when 0.6 kg of coal is burnt is _______.

Given below are the critical temperatures of some of the gases :

GasCritical temperature (K)
He5.2
CH4190.0
CO2304.2
NH3405.5

The gas showing least adsorption on a definite amount of charcoal is