d and f BLOCK ELEMENTS

What reagent is used to acidify the sodium chromate solution in the preparation of sodium dichromate?

• Hydrochloric acid (HCl)
• Nitric acid (HNO3)
• Sulphuric acid (H2SO4)
• Acetic acid (CH3COOH)

What is the color of the solution obtained after filtering the product of the chromite fusion reaction?

• Orange
• Green
• Yellow
• Purple

What is the role of air (O2) in the fusion reaction of chromite ore with sodium carbonate?

• It provides heat for the reaction
• It acts as a catalyst
• It acts as an oxidizing agent to convert Cr(III) to Cr(VI)
• It acts as a reducing agent

What is the immediate product formed when chromite ore is fused with sodium carbonate and air?

• Sodium dichromate (Na2Cr2O7)
• Potassium chromate (K2CrO4)
• Sodium chromate (Na2CrO4)
• Chromium metal

What is the primary source material for the industrial preparation of potassium dichromate?

• Chromium metal
• Potassium chromate
• Chromite ore (FeCr2O4)
• Manganese dioxide