MDCAT Chemistry MCQ #5390

When an aluminum container is used to transport concentrated Nitric acid, the metal does not dissolve. What mechanism explains this chemical passivity?

MDCAT Chemistry MCQ #5390

  1. Question 1

    Q1. When an aluminum container is used to transport concentrated Nitric acid, the metal does not dissolve. What mechanism explains this chemical passivity?

    • A) Formation of Aluminum nitrate
    • B) Formation of a protective oxide layer
    • C) Reduction of acid to Hydrogen gas
    • D) Rapid dissolution of the metal

    Answer: Formation of a protective oxide layer

    Explanation: Concentrated Nitric acid renders Aluminum passive by forming an oxide layer; dilute acid is tempting but actually reacts to release nitrogen oxides.