Which of the following statements about hydrogen is incorrect?

Water gas is _____________

The cause of permanent hardness of water is due to _____________

Zeolite used to soften hardness of water is hydrated _____________

A commercial sample of hydrogen peroxide marked as 100 volume H₂O₂, it means that _____________

The reaction H₃PO₂ + D₂O ➝ H₂DPO₂ + HDO indicates that hypo-phosphorus acid is _____________

In solid ice, oxygen atom is surrounded _____________

Assertion: Permanent hardness of water is removed by treatment with washing soda.
Reason: Washing soda reacts with soluble calcium and magnesium chlorides and sulphates in hard water to form insoluble carbonates

Find the wrong statement

Lithium shows diagonal relationship with _____________

Write a note on Haber's process.

What is Hydrogenation?

What are the advantages of using hydrogen as fuel?

Complete the following reactions and balance them:
(i) CO_(g) + H_2(g)➝
(ii) CH_4(g) + H₂O_(g) \(\overset { 1270K }{ \underset { Ni }{ \rightarrow } } \)

What happens when steam is passed over hot iron.

Explain the reaction of water with halogens.

What causes hardness in water?

What is Heavy water?

How is plaster of paris prepared ?

Give the uses of gypsum.

Compare the structures of H₂O and H₂O₂ .

Illustrate the industrial applications of hydrogen depending on 
(i) The heat liberated when its atoms are made to combine on the surface of metal.
(ii) Its effect on unsaturated organic system.
(iii) Its ability to combine with nitrogen under specific conditions.

Discuss the the uses of hydrogen.

Difference between ortho and para hydrogen

An element (A) belonging to group number 1 and period number 3 react with dihydrogen to form anhydride (B). The element (A) reacts with the universal solvent to give a strong base (C). Identify A, B, and C.

Identify the compound (A) which is a universal solvent. Compound A reacts with chlorine gas to give B and C. Compound A dissolves in an ionic compound of silicon to give compound D. Identify A and write the equations involved in the formation of B, C, and D.

Compound A is an important peroxide which disproportionates to give oxygen and water. Compound A reacts with ferrous sulphate under the acidic condition to give compound B. Compound A reacts with KMnO₄ in basic condition to form (C) and (D) along with water and CO₂ What are A, B, C and D ? Write down the equations involved in their formation.

An element (A) which is used in metallurgy for the reduction of metal oxide to metal reacts with carbon monoxide and forms an industrial solvent (B). The industrially produced element (A) reacts with nitrogen to form compound (C). Identify A, B, and C.

Dihydrogen reacts with dioxygen (O₂) to form water. Write the name and formula of the product when the isotope of hydrogen which has one proton and one neutron in its nucleus is treated with oxygen. Will the reactivity of both the isotopes be the same towards oxygen? Justify your answer.

When the first element of the periodic table is treated with dioxygen, it gives a compound whose solid state floats on its liquid state. This compound has an ability to act as an acid as well as a base. What products will be formed when this compound undergoes autoionisation ?