Question

What is the formula of diaspore? (a) \(\mathrm{AlPO}_{4}\) (b) \(\mathrm{Al}_{2} \mathrm{O}_{3} \cdot \mathrm{H}_{2} \mathrm{O}\) (c) \(\mathrm{Al}_{2} \mathrm{O}_{3}\) (d) \(\mathrm{Al}_{2} \mathrm{O}_{3} \cdot 2 \mathrm{H}_{2} \mathrm{O}\)

Short answer

The formula for diaspore is \(\mathrm{Al}_{2} \mathrm{O}_{3} \cdot \mathrm{H}_{2} \mathrm{O}\) (option b).

Step-by-step solution

Understanding the Question

We need to identify the chemical formula of a mineral called 'diaspore' from the given options.

Understanding Diaspore

Diaspore is a mineral that is composed of aluminum, oxygen, and hydrogen. This information is crucial for selecting the correct chemical formula.

Analyzing the Options

We examine each option: - (a) \(\mathrm{AlPO}_{4}\) contains phosphorus and does not fit our understanding of diaspore.- (b) \(\mathrm{Al}_{2} \mathrm{O}_{3} \cdot \mathrm{H}_{2} \mathrm{O}\) consists of aluminum, oxygen, and hydrogen, which matches the composition of diaspore.- (c) \(\mathrm{Al}_{2} \mathrm{O}_{3}\) lacks hydrogen, which means it cannot be diaspore.- (d) \(\mathrm{Al}_{2} \mathrm{O}_{3} \cdot 2 \mathrm{H}_{2} \mathrm{O}\) has two moles of water, which does not match the typical diaspore formula.

Selecting the Correct Option

From the above analysis, option (b) \(\mathrm{Al}_{2} \mathrm{O}_{3} \cdot \mathrm{H}_{2} \mathrm{O}\) is identified as the correct formula for diaspore because it includes one mole of water and matches the typical composition of diaspore.

Key concepts

mineral identification

Understanding how to identify minerals is a crucial skill in geology and chemistry.
Minerals are naturally occurring, solid substances with a definite chemical composition and crystalline structure.
The process of mineral identification involves examining various properties such as color, luster, hardness, and chemical composition.

For instance, diaspore is a mineral commonly identified by its presence of aluminum, oxygen, and hydrogen.

• **Color and Appearance:** Diaspore generally appears in varying hues from colorless to yellowish-white.
• **Luster:** This mineral showcases a vitreous (glassy) luster.
• **Hardness:** On the Mohs scale, diaspore has a hardness between 6.5 to 7, making it relatively hard.

All these properties together, including its chemical composition, help in reliably identifying diaspore from other minerals.

chemical formula

The chemical formula of a mineral is a symbolic representation that shows the elements present in the smallest unit of the substance and their ratios.
It is an essential component in chemistry as it provides a concise way to express the composition of a compound.

In the exercise, the task was to find the chemical formula of diaspore.
The chemical formula for diaspore is \(\mathrm{Al}_{2} \mathrm{O}_{3} \cdot \mathrm{H}_{2} \mathrm{O}\) which reveals the presence of aluminum, oxygen, and hydrogen.

• **Aluminum (Al):** This element is fundamental in diaspore's structure.
• **Oxygen (O):** Present in both the oxide and hydroxide components.
• **Water (H₂O):** The inclusion of one mole of water signifies its hydroxide nature.

This formula tells us not only what elements are present but also how they combine to give diaspore its unique properties.

aluminum oxide hydroxide

Aluminum oxide hydroxides are a family of minerals containing aluminum, oxygen, and hydroxide groups.
These minerals are significant in various industrial applications and geological formations.

Diaspore, an aluminum oxide hydroxide, has the chemical formula \(\mathrm{Al}_{2} \mathrm{O}_{3} \cdot \mathrm{H}_{2} \mathrm{O}\). This means it combines both oxide and hydroxide forms of aluminum.

• **Oxide Component:** The \(\mathrm{Al}_{2} \mathrm{O}_{3}\) part represents aluminum oxide.
• **Hydroxide Group:** One molecule of water indicates it is an oxide with a hydroxide component.
• **Applications:** It's used in producing refractory materials and as an abrasive due to its hardness.

Understanding this composition is crucial for mineralogists and chemists as it affects how the mineral reacts and behaves in different environments.