List of top Chemistry Questions

Correct statements among $a$ to $d$ regarding silicones are : (a) They are polymers with hydrophobic character (b) They are biocompatible. (c) In general, they have high thermal stability and low dielectric strenth. (d) Usually, they are resistant to oxidation and used as greases.

Iodine reacts with concentrated ${HNO_3}$ to yield $Y$ along with other products. The oxidation state of iodine in $Y$, is :

Ethylamine ${(C2H5NH2)}$ can be obtained from N-ethylphthalimide on treatment with :

Hinsberg's reagent is :

The volume of a closed reaction vessel in which the following equilibrium reaction occurs is halved: \[ 2SO_2(g) + O_2(g) \rightleftharpoons 2SO_3(g) \] \text{As a result,}

A coordination complex compound of cobalt has the molecular formula containing five ammonia molecules, one nitro group and two chlorine atoms for one cobalt atom. One mole of this compound produces three mole ions in an aqueous solution; on reacting with excess of \( \text{AgNO}_3 \), \( \text{AgCl} \) is precipitated. The ionic formula for this complex would be:

An endothermic reaction with high activation energy for the forward reaction is given by the diagram:

In a hydrogen-oxygen fuel cell, combustion of hydrogen occurs to:

An alkene of molecular formula \( C_9H_{18} \) on ozonolysis gives \( 2 \)-dimethylpropanal and \( 2 \)-butanone, then the alkene is:

Glucose when heated with \( CH_3OH \) in presence of dry HCl gas gives \( \alpha \)- and \( \beta \)-methyl glucosides because it contains:

When acetylene is passed into methanol at 160-200°C in the presence of a small amount of potassium methoxide under pressure, the following is formed:

Which compound can exist in a dipolar (zwitter) state?

Among the following molecules, those having the same number of lone pairs on Xe are: (i) \( XeO_3 \) (ii) \( XeOF_4 \) (iii) \( XeF_6 \)

Calculate the energy needed to convert three moles of sodium atoms in the gaseous state to sodium ions. The ionization energy of sodium is 495 kJ/mol:

In the reaction, \( C_6H_5OH + NaOH \rightarrow \) (B) \( \rightarrow (C) \), the compound (C) is:

Choose the complex which is paramagnetic:

Phosphine is generally prepared in the laboratory:

The uncertainty in position and velocity of a particle are \( 10^{-10} \, \text{m} \) and \( 5.27 \times 10^{-24} \, \text{ms}^{-1} \) respectively. Calculate the mass of the particle is (h = \( 6.625 \times 10^{-34} \, \text{Js} \)):

The rate constant is doubled when temperature increases from 27°C to 37°C. Activation energy in kJ is:

Which are the starting materials for the preparation of the compound shown in the figure?

An organic compound 'A' has the molecular formula \( C_3H_6O \), it undergoes iodoform test. When saturated with dil. HCl it gives 'B' of molecular formula \( C_9H_{14}O \). A and B respectively are:

Here Z is

Which element gives the maximum number of oxides?

The reaction \( 2NO(g) + O_2(g) \rightarrow 2NO_2(g) \) is of first order. If volume of the reaction vessel is reduced to \( \frac{1}{3} \) times, the rate of reaction would be: