List of top Chemistry Questions

A student needs to prepare a buffer solution of propanoic acid and its sodium salt with pH 4. The ratio of 
\(\frac{[CH_3CH_2COO^−]}{[CH_3CH_2COOH] }\)
required to make buffer is _____.
Given : Ka(CH3CH2COOH) = 1.3 × 10–5

Using the rules for significant figures, the correct answer for the expression
\(\frac{0.02858 × 0.112}{ 0.5702}\)
will be

In isolation of which one of the following metals from their ores, the use of cyanide salt is not commonly involved?

Among Co3+, Ti2+, V2+ and Cr2+ ions, one if used as a reagent cannot liberate H2 from dilute mineral acid solution, its spin-only magnetic moment in gaseous state is________ B.M. (Nearest integer)

Match List-I with List-II.

List-IList-II
(A) N2(g) + 3H2(g) → 2NH3(g)(I) Cu
(B) CO(g) + 3H2(g) → CH4(g) + H2O(g)(II) Cu/ZnO – Cr2O3
(C) CO(g) + H2(g) → HCHO(g)(III) FexOy + K2O + Al2O3
(D) CO(g) + 2H2(g) → CH3OH(g)(IV) Ni

Choose the correct answer from the options given below :

The photochemical smog does not generally contain :

20 mL of 0.1 M NH4OH is mixed with 40 mL of 0.05 M HCl.The pH of the mixture is nearest to(Given :Kb(NH4OH) = 1×10–5,log2 = 0.30,log3 = 0.48, log5 = 0.69,log7 = 0.84,log11 = 1.04)

During the denaturation of proteins, which of these structures will remain intact?

Choose the correct order of density of the alkali metals.

Most stable product of the following reaction is :
Most stable product

A compound’A’ on reaction with ‘X’ and ‘Y’ produces the same major product but differentby product’a’ and ‘b’. Oxidation of’a’ gives a substance produced by ants.

The compound(s) that is(are) removed as slag during the extraction of copper is
(A)CaO,(B)FeO,(C)Al2O3,(D)ZnO,(E)NiO
Choose the correct answer from the options given below :

Which one of the following reactions does not represent correct combination of substrateand product under the given conditions?

Drugs used to bind to receptors, inhibiting its natural function and blocking a message are called:

The enthalpy of combustion of propane, graphite and dihydrogen at 298 K are –2220.0 kJ mol–1, –393.5 kJ mol–1 and –285.8 kJ mol–1, respectively. The magnitude of enthalpy of formation of propane (C3H8) is _____ kJ mol–1. (Nearest integer)

The geometry around boron in the product ‘B’ formed from the following reaction is

Melamine polymer is formed by the condensation of :

The IUPAC nomenclature of an element with electronic configuration [Rn] 5f146d17s2 is

The interhalogen compound formed from the reaction of bromine with excess of fluorine is a :

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 ________

The reaction of H2O2 with potassium permanganate in acidic medium leads to the formation of mainly

Consider the ions/molecules \(O^{2+}, O_2, O_2^-, O_2^{2-}\)For increasing bond order the correct option is
Fig.

 

 

 



In the above reaction ‘A’ is

The spin only magnetic moment of the complex present in Fehling’s reagent is_____ B.M. (Nearest integer).
An acidified manganate solution undergoes disproportionation reaction. The spin-only magnetic moment value of the product having manganese in higher oxidation state is ____ B.M. (Nearest integer)