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Oxides, peroxides, superoxides and hydroxides

28 questions on Oxides, peroxides, superoxides and hydroxides from the s-Block Elements chapter: 6 NEET level, 11 JEE Main, 11 JEE Advanced. Each one opens with its answer and solution.

Practice this topic All s-Block Elements topics

Which oxide is the main product when sodium is burnt in excess air or oxygen? NEET level
Which of the following compounds is paramagnetic? NEET level
When lithium is burnt in air, the main oxygen-containing product is: NEET level
Among the hydroxides of alkali metals, the strongest base is: NEET level
The chemical formula of slaked lime is: NEET level
The oxidation state of oxygen in potassium superoxide, KO2, is: NEET level
Sodium peroxide reacts with ice-cold water to form: JEE Main level
Potassium superoxide absorbs carbon dioxide as 4KO2 + 2CO2 -> 2K2CO3 + 3O2. The number of moles of O2 released per mole of CO2 absorbed is: JEE Main level
Assertion (A): Be(OH)2 dissolves both in dilute HCl and in aqueous NaOH. Reason (R): Be(OH)2 is amphoteric. JEE Main level
Assertion (A): KO2 is paramagnetic. Reason (R): The superoxide ion O2^- has two unpaired electrons. JEE Main level
Match the compound in Column I with the oxygen species it contains in Column II. Column I: P Li2O, Q Na2O2, R KO2, S KO3. Column II: 1 O^2-, 2 O2^2-, 3 O2^-, 4 ... JEE Main level
Which hydroxide has the lowest solubility in water at 298 K among the following? JEE Main level
Which oxide is the most strongly basic among the following? JEE Main level
Chromium(III) hydroxide is warmed with Na2O2 in alkaline medium: 2Cr(OH)3 + 3Na2O2 -> 2Na2CrO4 + 2NaOH + 2H2O. The chromium-containing product has chromium in o... JEE Main level
Which alkali metal hydroxide gives the oxide when heated strongly, 2MOH -> M2O + H2O, at a moderate temperature while the others are stable? JEE Main level
Magnesium is burnt in air and the white residue is dropped into warm water. The gas evolved that turns moist red litmus blue is: JEE Main level
In metallurgy, CaO is added to remove silica from the ore as a slag. The slag is: JEE Main level
Consider the anions present in Na2O2 and KO2. Select the correct statement(s). JEE Advanced level
A metal X burns in excess air to give a pale yellow solid Y, which reacts with cold water to give a base and H_2O_2, and with CO2 to give a carbonate and oxygen... JEE Advanced level
Select the correct statement(s) about the hydroxides of Group 2 elements. JEE Advanced level
Select the correct statement(s) about lithium and its compounds. JEE Advanced level
Select the correct statement(s). JEE Advanced level
A pale yellow solid A is formed when sodium burns in excess air. A reacts with ice-cold dilute H2SO4 to give Na2SO4 and a compound B. B alone is then used to de... JEE Advanced level
Potassium in excess oxygen gives an orange-yellow paramagnetic solid X, whereas sodium heated in air gives a pale yellow diamagnetic solid Y. The ratio (bond or... JEE Advanced level
11.2 g of quicklime (CaO, molar mass 56 g mol^-1) is slaked completely with water. The resulting hydroxide is treated with excess chlorine at 313 K to form blea... JEE Advanced level
A sample of 2.5 g of BeO (molar mass 25 g mol^-1) is dissolved completely in excess aqueous NaOH to form Na2[Be(OH)4]. The mass of NaOH (40 g mol^-1) consumed i... JEE Advanced level
Caesium forms a stable superoxide CsO2 in excess oxygen, whereas lithium gives only Li2O and LiO2 is not obtained under normal conditions. The best explanation ... JEE Advanced level
A mixture of 5.85 g of Na2O2 and 6.39 g of KO2 is treated with excess CO2. Molar masses: Na2O2 78, KO2 71 g/mol; molar volume at STP is 22.4 L/mol. Calculate th... JEE Advanced level