Question

What is the formula of pyrolusite ore?

• A. PbCrO₄
• B. Cu₂O
• C. Cr₂O₃
• D. MnO₂

Hint:

Pyrolusite is a manganese ore with the formula \( \text{MnO}_2 \), and it is primarily composed of manganese dioxide.

Answer 1

The Correct Option is D

Step 1: Understanding pyrolusite ore.
Pyrolusite is an important manganese ore, and its formula is \( \text{MnO}_2 \). It consists mainly of manganese dioxide.
Step 2: Analyzing the options.
(A) PbCrO₄: Incorrect, this is the formula of chrome yellow.
(B) Cu₂O: Incorrect, this is the formula of copper(I) oxide.
(C) Cr₂O₃: Incorrect, this is the formula of chromium(III) oxide.
(D) MnO₂: Correct — This is the formula of pyrolusite ore.
Step 3: Conclusion.
The correct answer is (D) MnO₂.