What is the formula of pyrolusite ore?

What is the formula of pyrolusite ore?
  1. $\mathrm{PbCrO}_{4}$
  2. $\mathrm{Cu}_{2} \mathrm{O}$
  3. $\mathrm{Cr}_{2} \mathrm{O}_{3}$
  4. $\mathrm{MnO}_{2}$

Solution

Pyrolusite is a mineral consisting essentially of manganese dioxide (MnO2) and is important as an ore of manganese

Asked in: MHT CET 2020 (14 Oct Shift 2)

Practice more General Principles and Processes of Isolation of Metals questions on Aicharya