Problem 113 - A Complete Resource Book in Chemistry for JEE Main

Question

Match the following: List I List II 1\. Sorel's cement (i) \(\mathrm{MgCl}_{2}\) 2\. Albite (ii) \(\mathrm{MgO}\) 3\. A salt of carnalite (iii) \(\mathrm{NaAlSi}_{3} \mathrm{O}_{8}\) 4\. Glauber's salt (iv) \(\mathrm{Na}_{2} \mathrm{SO}_{4} \cdot 10 \mathrm{H}_{2} \mathrm{O}\) The correct matching is: \(\begin{array}{llll}1 & 2 & 3 & 4\end{array}\) (a) (ii) (iii) (iv) (i) (b) (iv) (ii) (ii) (i) (c) (iii) (ii) (i) (iv) (d) (ii) (iii) (i) (iv)

Step-by-Step Solution

Answer

The correct match is (d): 1-ii, 2-iii, 3-i, 4-iv.

Step 1: Identifying Components in List I

Let's start by analyzing List I. We have four items to match: (1) Sorel's cement, (2) Albite, (3) A salt of carnalite, and (4) Glauber's salt. Each of these is a chemical compound or mineral with a specific formula associated with it.

Step 2: Identifying Formulas in List II

Next, examine List II, which contains the formulas: (i) \(\mathrm{MgCl}_{2}\), (ii) \(\mathrm{MgO}\), (iii) \(\mathrm{NaAlSi}_{3} \mathrm{O}_{8}\), and (iv) \(\mathrm{Na}_{2} \mathrm{SO}_{4} \cdot 10 \mathrm{H}_{2} \mathrm{O}\). We need to match these formulas to the items in List I.

Step 3: Match Sorel's Cement

Sorel's cement is a type of magnesium cement primarily composed of magnesium oxide and magnesium chloride. Thus, it matches with (ii) \(\mathrm{MgO}\) and (i) \(\mathrm{MgCl}_{2}\), but in this context it closely matches \(\mathrm{MgO}\) (ii) as Sorel's cement refers to a combination of elements with \(\mathrm{MgO}\) being a key component.

Step 4: Match Albite

Albite is a mineral from the feldspar group, characterized by the formula \(\mathrm{NaAlSi}_{3} \mathrm{O}_{8}\). Hence, it matches with (iii) \(\mathrm{NaAlSi}_{3} \mathrm{O}_{8}\).

Step 5: Match A Salt of Carnalite

Carnalite is a mineral composed of hydrated potassium magnesium chloride. It generally relates to a complex salt, but a simpler component yet representative is \(\mathrm{MgCl}_{2}\). So, the match is with (i) \(\mathrm{MgCl}_{2}\).

Step 6: Match Glauber's Salt

Glauber's salt is commonly known as sodium sulfate decahydrate, which corresponds to the chemical formula \(\mathrm{Na}_{2} \mathrm{SO}_{4} \cdot 10 \mathrm{H}_{2} \mathrm{O}\). Therefore, it matches with (iv) \(\mathrm{Na}_{2} \mathrm{SO}_{4} \cdot 10 \mathrm{H}_{2} \mathrm{O}\).

Step 7: Compile the Matches

With all the individual components matched, compile them as:1. Sorel's cement - (ii) \(\mathrm{MgO}\)2. Albite - (iii) \(\mathrm{NaAlSi}_{3} \mathrm{O}_{8}\)3. A salt of carnalite - (i) \(\mathrm{MgCl}_{2}\)4. Glauber's salt - (iv) \(\mathrm{Na}_{2} \mathrm{SO}_{4} \cdot 10 \mathrm{H}_{2} \mathrm{O}\)This corresponds to option (d).

Key Concepts

Sorel's Cement

Sorel's cement, also known as magnesia cement, is an important type of magnesium-based cement. It was first discovered by the French chemist Stanislas Sorel in the 19th century. This unique material is mainly made from magnesium oxide (MgO) and magnesium chloride (MgCl₂). Its formation involves a chemical reaction between these two components, resulting in a hardening product useful in construction.

• Composition: The critical ingredients of Sorel's cement are magnesium oxide (MgO) and magnesium chloride (MgCl₂). When these are combined, they undergo a chemical process forming the cementitious compound known as magnesium oxychloride.
• Uses: Sorel's cement is known for its quick setting time and superior bonding capabilities. This makes it particularly suitable for applications like flooring materials, fireproofing, and protective coatings for metals.
• Properties: It possesses high compressive strength and resistance to abrasion, but it might be less resistant to water compared to Portland cement. Therefore, it is less popular in areas exposed to moisture.

Understanding Sorel's cement is essential for recognizing its potential uses in various industries, primarily due to its unique properties and the role of magnesium oxide.

Albite

Albite is a fascinating mineral from the feldspar group, known for its beautiful crystalline structure. It is a type of plagioclase feldspar with a sodium-aluminum-rich chemical composition.

• Chemical Formula: The formula for Albite is NaAlSi₃O₈. Its formation involves the arrangement of sodium, aluminum, silicon, and oxygen atoms.
• Appearance: This mineral typically appears in white or colorless crystal forms. However, it can also display shades of blue, green, red, or yellow based on impurities.
• Occurrence: Albite is commonly found in igneous rocks such as granites and syenites. It can also be present in metamorphic rocks.
• Uses: In addition to its role as a gemstone, Albite is used in glass and ceramic industries due to its desirable properties like low melting point and fusibility.

Albite's properties and wide occurrence make it an important mineral for geological and industrial purposes.

Carnalite

Carnalite is a unique mineral known for its importance in potassium and magnesium chemical industries. It stands out as a hydrous chloride mineral that primarily consists of two essential metallic elements.

• Composition: Its composition is often represented as KMgCl₃·6H₂O, consisting of potassium, magnesium, and chloride ions along with water of crystallization.
• Properties: Carnalite typically presents as an evaporite mineral, meaning it forms by the evaporation of saline waters. It has a white to reddish color and is soluble in water.
• Usage: Carnalite is highly valued for extracting potassium, which is essential for fertilizer production. It also provides magnesium for various industrial applications.
• Mineral Extraction: Due to its solubility, extracting components from carnalite is typically achieved through a process known as solution mining.

Recognizing its ability to provide crucial elements deeply connects carnalite to the agricultural and chemical sectors.

Glauber's Salt

Glauber's Salt, otherwise known as sodium sulfate decahydrate, is a historic compound with a variety of uses in different industries. Its role spans from traditional medicine to modern manufacturing.

• Chemical Structure: The chemical formula for Glauber's Salt is Na₂SO₄·10H₂O, indicating that it contains water molecules within its crystalline structure.
• Historical Uses: Named after Johann Rudolf Glauber, who discovered it in the 17th century, it was originally used as a laxative due to its effective action in the digestive system.
• Modern Applications: Today's applications include use in the manufacture of textiles and paper, where it is valued for its role in the Kraft process.
• Properties: As a decahydrate, Glauber's Salt is known for losing water molecules upon heating, a property that is utilized in laboratory and industrial settings.

Glauber's Salt continues to be a compound of interest due to its versatility and historical significance in chemistry.