Question

Identify the Manganese containing minerals
(A). Pyrolusite
(B). Malachite
(C). Manganite
(D). Goethite
Choose the correct answer from the options given below:

• A. Only A & B
• B. Only B & C
• C. Only A & C
• D. Only B & D

Hint:

The name "Manganite" directly points to the element Manganese (\(\text{Mn}\)).
Pyrolusite (\(\text{MnO}_2\)) is the most common mineral form of manganese in the Earth's crust.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Minerals are naturally occurring, inorganic crystalline solids with definite chemical compositions.
Identifying the chemical composition of soil minerals is essential to understand nutrient release and weathering pathways.

Step 2: Detailed Explanation:
Let us analyze the chemical composition of each mineral listed:
- (A). Pyrolusite: This is a primary manganese mineral consisting of manganese dioxide (\(\text{MnO}_2\)).
It is the most common and economically important ore of manganese.
Thus, (A) is a manganese-containing mineral.
- (B). Malachite: This is a carbonate mineral of copper, chemically formulated as basic copper carbonate (\(\text{Cu}_2\text{CO}_3(\text{OH})_2\)).
It is a major ore of copper, not manganese.
- (C). Manganite: This is an oxide-hydroxide mineral of manganese, chemically formulated as manganese oxide-hydroxide (\(\text{MnO(OH)}\)).
Thus, (C) is a manganese-containing mineral.
- (D). Goethite: This is an iron-bearing oxide-hydroxide mineral, chemically formulated as iron oxide-hydroxide (\(\text{FeO(OH)}\)).
It is one of the most common constituents of soil rust and a major iron ore, not manganese.
Therefore, only Pyrolusite (A) and Manganite (C) contain manganese.

Step 3: Final Answer:
The manganese-containing minerals are Only A & C.