Chemistry Questions & Answers (Compiled from UPSC, SSC ,PSC ,IBPS previous question papers)

During the electrolysis of molten sodium chloride, the time required to produce 0.10 mol of chlorine gas using a current of 3 amperes is

The decomposition of phosphine (PH3) on tungsten at low pressure is a first-order reaction. It is because the

The molar conductivity of a 0.5 mol/ dm3 solution of AgNO3 with electrolytic conductivity of 5.76 × 10^–3 S cm^–1 at 298 K is

Which one of the following compounds shows the presence of intramolecular hydrogen bond ?

The compound that will react most readily with gaseous bromine has the formula :

Which among the give nmolecules can exhibit tautomerism?

The correct structure of the product A formed in the reaction:

Consider the reaction :

CH₃CH₂CH₂Br + NaCN  → CH₃CH₂CH₂CN + NaBr

This reaction will be the fastest in :

A given nitrogen-containing aromatic compound A reacts with Sn/HCl, followed by HNO₂ to give an unstable compound B. B, on treatment with phenol, forms a beautiful coloured compound C with the molecular formula C₁₂H₁₀N₂O. The structure of compound A is :

Iron and manganese are removed in water by the process of:

Consider the following four particles :

1. Alpha particle
2. Proton
3. Electron
4. Neutron

Which of the following is the correct sequence in which their rest-masses increase?

Which among the following thermometers is preferred for measuring temperature around 1250°C?

One light year is equal to

The resistance of a wire that must be placed parallel with a 12 Ω resistance to obtain a combined resistance of 4 Ω is

Non-conductors, whose polarization is caused by an electric field, are known as

Which one of the following chemicals is used in beauty parlours for hair-setting?

Two elements gallium and oxygen combine to form a compound Ga₂O₃. Which among the following is the valency of gallium?

Match List I with List II and select the correct answer using the code given below the lists

Which one of the following contains maximum percentge of nitrogen by mass?

Which one of the following is used as moderator in nuclear reactors?

Consider the following equation for the formation of ammonia from nitrogen and hydrogen :

N₂+ 3H₂ = 2NH₃

How many hydrogen molecules are required to react with 100 molecules of nitrogen?

Which among the following is an element

Which among the following is a chemical change?

Which among the following is the major constituent of soda lime glass?

Which one among the following is the most appropriate statement with respect to the atomic weight of an element?

Which one among the following transitions of electron of hydrogen atom emits radiation of the shortest wavelength?

 Which one among the following is the correct order of amount of lime (CaO), silica (SiO₂), alumina (Al₂O₃) and ferric oxide (Fe₂O₃) in Portland cement

Which one among the following nitrogen compounds has the least percentage of nitrogen by mass

The following equation is an example of a redox reaction, in which Cl2 is the oxidizing agent and FeBr3 is the reducing agent:

2FeBr₃(aq) + 3Cl₂(g) = 2FeCl₃(aq) + 3Br₂(l)
Which one among the following statements if incorrect for this redox reaction?