Question 1

Identify the catalyst used to transform carbon monoxide from water gas into carbon dioxide

Accepted Answer

The reaction of carbon monoxide of water gas (syngas) with steam to form carbon dioxide and dihydrogen is called the water-gas shift reaction. CO(g) + H _2 O(g) Iron chromate, 673 K CO _2 (g) + H _2 (g) The catalyst used in this process is iron chromate. Answer: Iron chromate

Question 2

Which from following oxides is amphoteric in nature?

Accepted Answer

BaO is an oxide of an alkaline earth metal and is basic in nature. N _2 O _5 and CO _2 are oxides of non-metals and are acidic in nature. Al _2 O _3 reacts with both acids and bases to form salt and water, exhibiting both acidic and basic properties. Hence, it is an amphoteric oxide. Reaction with acid: Al _2 O _3 + 6 HCl 2 AlCl _3 + 3 H _2 O Reaction with base: Al _2 O _3 + 2 NaOH + 3 H _2 O 2 Na [ Al ( OH )_4] Answer: Al _2 O _3

Question 3

What is the formula of Tin (IV) oxide?

Accepted Answer

The oxidation state of Tin (Sn) in Tin (IV) oxide is +4. The oxidation state of Oxygen (O) in an oxide ion is -2. To form a neutral compound, the total positive charge must balance the total negative charge. Two oxide ions are required to balance one Tin (IV) ion. Using the criss-cross method, the formula is initially Sn _2 O _4, which simplifies to the empirical formula SnO _2. Answer: SnO _2

Question 4

Which from the following is NOT polymorphic form of silica ?

Accepted Answer

Silica (SiO_2) exists in various polymorphic forms such as quartz ( -quartz and -quartz), cristobalite, and tridymite. Aragonite is a naturally occurring crystalline form of calcium carbonate (CaCO_3), not silica. Therefore, Aragonite is not a polymorphic form of silica. Answer: Aragonite

Question 5

What is the nature of Al _2 O _3?

Accepted Answer

Aluminium oxide ( Al _2 O _3) is an amphoteric oxide because it reacts with both acids and bases to form salt and water. Reaction with acid: Al _2 O _3 + 6 HCl 2 AlCl _3 + 3 H _2 O Reaction with base: Al _2 O _3 + 2 NaOH + 3 H _2 O 2 Na [ Al ( OH )_4] Thus, it is amphoteric in nature. Answer: Amphoteric

p Block Elements (Group 13 & 14) — Previous Year Questions & Solutions