Oxygen and Oxides Chemistry
Covers oxygen preparation, properties, tests, reactions with elements, combustion, oxide types (acidic, basic, amphoteric), and oxidation processes
Questions
Which of the following pairs belongs to the acidic oxide group?
- Carbon Dioxide/Sulphur Dioxide
- Nitrogen Dioxide/Nitric Oxide
- Carbon Dioxide/ Carbon Mono Oxide
- Phosphorous Penta Oxide /Water
Amphoteric oxide can react with
- acids
- alkalies
Choose the correct option.
- Reacts with acids only
- Reacts with alkalies only
- No reaction at all
- Reacts with acids as well as alkalies
- Do not react with acids and bases
Which element, when treated with oxygen, burns with dazzling flame followed by white fumes and the product formed, when treated with moist blue litmus, turns it red?
- Sulphur
- Sodium
- Magnesium
- Phosphorous
Which of the following nitrates does not liberate oxygen gas on heating?
- Sodium nitrate
- Lead nitrate
- Ammonium nitrate
- Silver nitrate
Which element, when burnt in the atmosphere of oxygen, emits a brilliant brick red flame and the product formed turns moist red litmus paper blue?
- Calcium
- Sodium
- Potassium
- Sulphur
Pb3O4, when heated, releases a gas leaving behind a pale yellow residue. Name the residue.
- Lead mono oxide
- Lead dioxide
- Both lead dioxide and mono oxide
- None of the above
In lab method, which substance is used as a raw material with catalyst MnO2 for the preparation of oxygen?
- Potassium chlorate
- Potassium chlorite
- Potassium perchlorate
- Potassium chloride
Electrolysis of water gives oxygen and hydrogen and it is used for the industrial preparation of oxygen and hydrogen. Which of the following is correct about the above process?
- Oxygen is obtained at anode and hydrogen is obtained at cathode.
- Electrolysis of acidulated water is done as pure water does not allow electricity to pass through it.
- Both answers are correct.
- Both the above options are wrong.
Why is it advantageous to use hydrogen peroxide than potassium chlorate for preparing oxygen in the lab method?
- As no heating is required, energy is saved.
- The evolution of oxygen can be controlled by regulating the tap of the dropping funnel.
- No catalyst is required, so it is a cheap process.
- Both (1) and (2)
What is true about cryogen, which is given in hospitals to stimulate natural breathing?
- It contains 100% oxygen.
- It contains about 95% oxygen and rest is carbon dioxide.
- It contains 50% oxygen, and rest is carbon dioxide.
- It contains 95% oxygen and rest is nitrogen.
Which is the correct order for decreasing reactivity of metals with oxygen?
- Na,Ca,Fe,Cu,Au
- Ca,Na,Fe,Cu,Au
- Na,Ca,Cu,Fe,Au
- Na,Ca,Fe,Au,Cu
Hydrocarbons are organic compounds that contain carbon and hydrogen. What are the products formed when they are burnt in excess of oxygen?
- Carbon and water
- Carbon monoxide and water
- Carbon dioxide and water
- All of the above
Which allotrope of oxygen is triatomic in nature?
- Ozone
- O2-
- Both are wrong
- Both are correct
Which of the following statements is correct?
- Oxygen is lighter than air, so it is collected by the downward displacement of air.
- Phosphorous penta oxide is a basic gas which turns moist red litmus solution blue
- Sulphur forms neutral oxide when burned in oxygen.
- Metals like aluminium and zinc burn in oxygen to form their respective oxides, which are amphoteric in nature.
Which of the following tests of oxygen is incorrect?
- It rekindles the glowing splinter.
- It turns colourless nitrogen monoxide into brown fumes.
- It turns alkaline pyrogallol dark brown.
- It turns moist blue litmus paper red.
When amphoteric oxide reacts with acids as well as bases to form salt and water, which of the following oxides is yellow when hot and white when cold?
- Lead oxide
- Calcium oxide
- Zinc oxide
- Aluminium oxide
Which of the following elements burns with pale blue flame in oxygen and the product formed has no action on blue litmus solution?
- Sulphur
- Carbon
- Hydrogen
- Sodium
An element X burns in atmosphere with shower of spark, forming the magnetic oxide of X. Which is the correct combination of metal and its oxide?
- Al and Al2O3
- Pb and Pb3O4
- Fe and Fe3O4
- Zn and ZnO
Which product is used for drying of oxygen in laboratory?
- Phosphorous pentoxide
- Fused calcium chloride
- Conc. sulphuric acid
- All of the above
Which of the following statements is correct about burning and rusting?
- Both are chemical changes
- Air and moisture are necessary in both cases.
- Rusting is fast oxidation but burning is slow oxidation.
- Mass increases in both the cases
Which gas apart from oxygen supports combustion?
- Nitric oxide
- Nitrogen dioxide
- Nitrous oxide
- None of the above
What is true about the reaction N2 +O2 ---------> 2NO {presence of electric spark} that takes place in atmosphere at the time of lightning?
- The product formed is colourless, neutral and the reaction is endothermic.
- The product formed is reddish, neutral and the reaction is endothermic.
- The product formed is colourless, acidic and the reaction is endothermic.
- The product formed is colourless, neutral, and the reaction is exothermic.
Red lead when heated leaves behind a residue which is reddish brown when hot and yellow when cold. It fuses with glass and also liberates a gas which rekindles a glowing splinter. Which residue is formed?
- It is lead mono oxide and acidic in nature.
- It is PbO2 and amphoteric in nature.
- It is Pb3O4 and amphoteric in nature.
- Residue is lead mono oxide and amphoteric in nature
Which solution turns dark brown when oxygen is passed through it?
- Nessler's reagent
- Alkaline potassium permanganate solution
- Alkaline pyrogallol
- Blue litmus
What products are formed when sulphur and sodium are burnt in sufficient oxygen?
- Acidic and basic oxides are formed, respectively.
- Both form acidic oxides.
- Both form basic oxides.
- They form neutral and acidic oxides, respectively.