d and f BLOCK ELEMENTS

What is the main reason acidified potassium dichromate can oxidize various substances like iodides, sulphides, and iron(II)?

• Because it is highly colored
• Because it is inexpensive
• Because dichromate is a strong oxidizing agent with a high positive reduction potential
• Because it is stable at high temperatures

Which of the following is a common application of sodium dichromate specifically mentioned in the text?

• As a food additive
• As a primary standard in volumetric analysis
• As an oxidizing agent in organic chemistry
• As a pigment in paints

What is the typical color of dichromate (Cr2O7^2-) salts in aqueous solution?

• Yellow
• Green
• Orange
• Purple

What is the typical color of chromate (CrO4^2-) salts in aqueous solution?

• Orange
• Green
• Yellow
• Blue

In the interconversion equilibrium 2 CrO4^2- + 2H+ <=> Cr2O7^2- + H2O, what effect does adding a base (OH-) have?

• It shifts the equilibrium to the right, favoring dichromate ion formation
• It shifts the equilibrium to the left, favoring chromate ion formation
• It has no effect on the equilibrium
• It stops the reaction completely