Liquor ammonia bottles are opened only after cooling. This is because

• it is only a mild explosive

• it is a corrosive liquid

• it is a lachrymatory

• it generates high vapour pressure and mild explosive

When plants and animals decay, the organic nitrogen is converted into inorganic nitrogen. The inorganic nitrogen is in the form of

• ammonia

• elements of nitrogen

• nitrates

• nitrides

The formation of O${}_2^{+}$[PtF₆]^- is the basis for the formation of xenon fluorides. This is because :

• O₂ and Xe have comparable size

• Both O₂ and Xe are gases

• O₂ and Xe have both comparable ionisation size energies and comparable sizes.

• O₂ and Xe have comparable electro- negativities.

The formula mass of Mohr's salt is 392. The iron present in it is oxidised by KMnO₄ in acid medium. The equivalent mass of Mohr's salt is :

• 392

• 31.6

• 278

• 156

The brown ring test for nitrates depends on :

• the reduction of nitrate to nitric oxide

• oxidation of nitric oxide to nitrogen dioxide

• reduction of ferrous sulphate to iron

• oxidising action of sulphuric acid

446.

An organic compound which produces a bluish green coloured flame on heating in presence of copper is :

• chlorobenzene

• benzaldehyde

• aniline

• benzoic acid

Acidified sodium fusion extract on addition of ferric chloride solution gives blood red colouration which confirms the presence of

• S and Cl

• N and S

• N

• S

The number of gram molecules of chlorine in 6.02 × 10²⁵ hydrogen chloride molecules is

• 10

• 100

• 50

• 5

When conc. H₂SO₄ is heated with P₂O₅, the acid is converted into

• sulphur trioxide

• sulphur dioxide

• sulphur

• a mixture of sulphur dioxie and sulphur trioxide

The noble gas mixture is cooled in a coconut bulb at 173 K. The gases that are not adsorbed are

• Ne and Xe

• He and Xe

• Ar and Kr

• He and Ne