Understanding Ores and Their Metals

This question asks us to match common ores listed in List I with the metals that are primarily extracted from them, listed in List II. Understanding the relationship between ores and the metals they contain is fundamental in chemistry and metallurgy.

Let's examine each ore in List I and determine the main metal associated with it:

• Siderite: Siderite is a mineral composed of iron(II) carbonate ($\text{FeCO}_3$). It is a significant ore of iron.
• Malachite: Malachite is a copper carbonate hydroxide mineral ($\text{Cu}_2\text{CO}_3(\text{OH})_2$). It is a common ore of copper.
• Calamine: Historically, Calamine referred to zinc carbonate ($\text{ZnCO}_3$) or zinc silicate ($\text{Zn}_4\text{Si}_2\text{O}_7(\text{OH})_2 \cdot \text{H}_2\text{O}$). Both are ores of zinc. In modern mineralogy, the term often refers specifically to Hemimorphite ($\text{Zn}_4\text{Si}_2\text{O}_7(\text{OH})_2 \cdot \text{H}_2\text{O}$). It is an important ore of zinc.
• Bauxite: Bauxite is not a single mineral but a rock composed primarily of aluminium hydroxide minerals, mainly gibbsite ($\text{Al(OH)}_3$), boehmite ($\text{AlO(OH)}$), and diaspore ($\text{AlO(OH)}$), mixed with oxides of iron and silicon. It is the primary ore used for aluminium production globally.

Matching Ores to Metals: Detailed Analysis

Now, let's match the ores from List I with the correct metals from List II based on our understanding:

List I (Ores)

1. Siderite
2. Malachite
3. Calamine
4. Bauxite

List II (Metals)

1. Aluminium
2. Iron
3. Copper
4. Zinc

Based on our analysis:

• Siderite is an ore of Iron. This matches A with II. ($\text{A} \rightarrow \text{II}$)
• Malachite is an ore of Copper. This matches B with III. ($\text{B} \rightarrow \text{III}$)
• Calamine is an ore of Zinc. This matches C with IV. ($\text{C} \rightarrow \text{IV}$)
• Bauxite is an ore of Aluminium. This matches D with I. ($\text{D} \rightarrow \text{I}$)

So, the correct matching sequence is A - II, B - III, C - IV, D - I.

Summary of Ore-Metal Matching

Revision Table: Common Ores and Metals

Additional Information on Ores and Metallurgy

An ore is a naturally occurring rock or sediment that contains one or more valuable minerals, typically containing metals, that can be mined, treated, and sold at a profit. Ores are extracted from the Earth through mining and then processed to extract the desired metal. This processing often involves steps like crushing, grinding, concentration (removing unwanted material called gangue), and extraction of the metal through chemical or electrochemical methods (like smelting or electrolysis).

Understanding the common ores of important metals is crucial for studying extraction processes and the properties of elements. The examples given in the question (Siderite, Malachite, Calamine, Bauxite) are classic examples frequently encountered in the study of metallurgy and mineral resources.