JEE Mains JEE Advance BITSAT
JEE Mains | PYQ

Year

All years 2023 2022 2021

High purity \(( > 99.95\%) \) dihydrogen is obtained by:

Which one of the following compounds is used as a chemical in certain type of fire extinguisher?

Boiling of hard water is helpful in removing the temporary hardness by converting calcium hydrogen carbonate and magnesium hydrogen carbonate to:

On reaction with stronger oxidizing agent like \( \text{KIO}_4 \), hydrogen peroxide oxidizes with the evolution of \( \text{O}_2 \). The oxidation number of \( \text{I} \) in \( \text{KIO}_4 \) changes to _______.

Given below are two statements:
Statement I: Hydrogen peroxide can act as an oxidizing agent in both acidic and basic conditions.
Statement II: Density of hydrogen peroxide at \( 298 \, \text{K} \) is lower than that of \( \mathrm{D_2O} \).
In the light of the above statements, choose the correct answer from the options given below:

Which one of the following alkaline earth metal ions has the highest ionic mobility in its aqueous solution?

In the industrial production of which of the following, molecular hydrogen is obtained as a byproduct?

Dihydrogen reacts with \( \mathrm{CuO} \) to give.

Which one of the following reactions indicates the reducing ability of hydrogen peroxide in basic medium?

The highest industrial consumption of molecular hydrogen is to produce compounds of element:

\( \mathrm{BeCl_2} \) reacts with \( \mathrm{LiAlH_4} \) to give:

Hydrogen has three isotopes: protium (\( {}^{1}\mathrm{H} \)), deuterium (\( {}^{2}\mathrm{H} \)) or \( \mathrm{D} \) and tritium (\( {}^{3}\mathrm{H} \) or \( \mathrm{T} \)). They have nearly same chemical properties but different physical properties. They differ in

The metal slats formed during softening of hardwater using Clark’s method are:

The products obtained during treatment of hard water using Clark’s method are”

Match List-I with List-II

Choose the correct answer from the options given below:

Which of the following statements are correct ?
(A) Both \( \mathrm{LiCl} \) and \( \mathrm{MgCl_2} \) are soluble in ethanol.
(B) The oxides \( \mathrm{Li_2O} \) and \( \mathrm{MgO} \) combine with excess of oxygen to give superoxide.
(C) \( \mathrm{LiF} \) is less soluble in water than other alkali metal fluorides.
(D) \( \mathrm{Li_2O} \) is more soluble in water than other alkali metal oxides.
Choose the most appropriate answer from the options given below:

The total number of monobromo derivatives formed by the alkanes with molecular formula \( \mathrm{C_5H_{12}} \) is (excluding stereo isomers) ________.

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 statements choose the most appropriate answer from the options given below:

BeO reacts with HF in presence of ammonia to give [A] which on thermal decomposition produces [B] and ammonium fluoride. Oxidation state of be in [A] is ______.

Two isomers 'A' and 'B' with molecular formula \( \mathrm{C}_4\mathrm{H}_8 \) give different products on oxidation with \( \mathrm{KMnO_4} \) in acidic medium. Isomer 'A' on reaction with \( \mathrm{KMnO_4} / \mathrm{H^+} \) results in effervescence of a gas and gives ketone. The compound 'A' is:

Which of the following can be used to prevent the decomposition of \( \mathrm{H_2O_2} \)?

← PreviousQuestion 19 of 21Next →

JEE Main 2022 27th June Evening Shift

BeO reacts with HF in presence of ammonia to give [A] which on thermal decomposition produces [B] and ammonium fluoride. Oxidation state of be in [A] is ______.