Chromium(III) Ion Reactions with Sodium Hydroxide

The video tutorial explains how to write a net ionic equation for the reaction between chromium(III) ions and sodium hydroxide. It covers identifying the products, balancing the molecular equation, assigning states to each substance, and deriving the complete and net ionic equations. The tutorial also highlights the practical application of this reaction in removing chromium from wastewater.

What are the products formed when chromium(III) ion reacts with sodium hydroxide?

• Chromium hydroxide and sodium ion

• Chromium sulfate and sodium chloride

• Chromium oxide and water

• Sodium chromate and water

How many hydroxide ions are needed to balance the charge of one chromium(III) ion?

• Four

• One

• Three

• Two

What is the role of sodium hydroxide in the reaction?

• It forms a gas

• It acts as a reducing agent

• It oxidizes chromium

• It provides hydroxide ions

What is the state of chromium(III) hydroxide in the reaction?

• Aqueous

• Solid

• Gas

• Liquid

What is the charge of the sodium ion in the reaction?

• Negative

• Positive

• Variable

• Neutral

Which of the following is a spectator ion in the reaction?

• Chromium(III) ion

• Hydroxide ion

• Sodium ion

• Chromium hydroxide

What is the net ionic equation for the reaction between chromium(III) ion and sodium hydroxide?

• Cr3+ + 3Na+ → Cr(OH)3

• Cr3+ + 3OH- → 3Na+

• Cr3+ + 3OH- → Cr(OH)3

• Cr3+ + OH- → Cr(OH)3

Why is it important to remove chromium from wastewater?

• Chromium enhances water taste

• Chromium is harmful to human health

• Chromium is beneficial for aquatic life

• Chromium is a valuable resource

What happens to sodium ions in the reaction?

• They form a solid

• They remain in solution

• They react with chromium

• They evaporate

What is the net charge of the compound formed in the reaction?

• Positive

• Negative

• Zero

• Variable