The chemical formula of 'tear gas' is

• COCl₂

• CO₂

• Cl₂

• CCl₃NO₂

Which of the following is not correct?

• Iodine oxidises sodium thiosulphate to sodium tetrathionate

• Sodium thiousulphate is soluble in water

• Ozone is used to identify the presence of unsaturation in alkenes

• Sodium thiosulphate reacts with iodine to form sodium sulphate

Which one of the following pairs of reactants does not form oxygen when they react with each other?

• F₂, NaOH solution (hot, conc.)

• F₂, H₂O

• Cl₂, NaOH solution (cold, dilute)

• CaOCl₂, H₂SO₄ (dilute, small amount)

What is the correct order of occurrence (% by weight) in air of Ne, Ar and Kr ?

• Ne > Ar > Kr

• Ar > Ne > Kr

• Ar > Kr > Ne

• Ne > Kr > Ar

Hydrolysis of NCl₃ gives NH₃ and X. Which of the following is X?

• HClO₄

• HClO₃

• HOCl

• HClO₂

What are the metal ions present in carnallite?

• Mg, K

• Al, Na

• Na, Mg

• Zn, Mg

Which of the following is not a peroxy acid ?

• Perphosphoric acid

• Pernitric acid

• Perdisulphuric acid

• Perchloric acid

Which one of the following reactions does not occur?

• F₂ + 2Cl^- → 2F^- + Cl₂

• Cl₂ + 2F^- → 2Cl^- + F₂

• Br₂ + 2I^- → 2Br^- + I₂

• Cl₂ + 2Br^- → 2Cl^- + Br₂

The formula of the product formed, when sodium thiosulphate solution is added to silver bromide is

• Ag₂S₂O₃

• Ag₂S

• Na₃[Ag(S₂O₃)₂]

• Ag₃[Na(S₂O₃)₂]

Which one of the following noble gases is used in miner's cap lamps ?

• Helium

• Neon

• Argon

• Krypton