Test for Gases [Ms Paik]

What gas is produced when dilute hydrochloric acid reacts with a metal?

• Nitrogen gas

• Carbon dioxide

• Oxygen gas

• Hydrogen gas

How can you test for the presence of oxygen gas?

• Lighted splint extinguishes with a 'pop' sound

• Lighted splint relights

• Glowing splint relights

• Glowing splint extinguishes with a 'pop' sound

Which gas forms white precipitate in lime water when passed through it?

• Nitrogen

• Hydrogen

• Oxygen

• Carbon dioxide

What is the expected color change of litmus paper when exposed to chlorine gas, Cl₂? [Multi-select]

• damp red litmus paper remained red, bleached white

• blue litmus paper turned red

• damp blue litmus paper turned red, bleached white

• damp red litmus paper turned blue, bleached white

How can you identify the presence of ammonia gas?

• Damp red litmus paper turned blue

• Damp blue litmus paper turned red

• red litmus paper turned blue

• blue litmus paper turned red

Which reaction leads to the formation of NH₃ gas?

• NH₄NO₃ + NaCl

• NH₃ + H₂O

• NH₄Cl + HCl

• NH₄Cl + NaOH

How can you test for the presence of carbon dioxide gas?

• Bubble the gas through lime juice (squeeze lime in water)

• Bubble the gas through quicklime (calcium oxide)

• Bubble the gas through limewater (calcium hydroxide)

• Bubble the gas through limestone (calcium carbonate)

Which reaction will lead to the production of carbon dioxide gas?

• HCl + Mg₂CO₃

• HNO₃ + MgCO₃

• NaOH + ZnCO₃

• KOH + ZnCO₂

What are the observations for the test of sulfur dioxide gas?

Answer explanation

Gas produced

decolourises the acidified purple

KMnO4 solution OR turns the

acidified purple KMnO4 solution

colourless.

Sulfur dioxide (SO2) is evolved.