Question

The mixture of ${\mathrm{MgCl}}_2$ and $\mathrm{MgO}$ is called (1) Sorrel's cement (2) Mixed salt (3) Portland cement (4) Magnesium oxychloride

Short answer

Magnesium oxychloride

Step-by-step solution

- Identify Components

Review the given chemical components in the mixture: ${\mathrm{MgCl}}_2$ and $\mathrm{MgO}$. Remember what each compound is and its common uses.

- Analyze Mixture

Consider what those two compounds form when mixed together. They combine to create a composite material.

- Match with Given Options

Compare the given mixture with the provided options. $$\text{(1) Sorrel's cement}\text{(2) Mixed salt}\text{(3) Portland cement}\text{(4) Magnesium oxychloride}$$ The correct matching is Magnesium oxychloride which is commonly made from ${\mathrm{MgCl}}_2$ and $\mathrm{MgO}$.

Key concepts

chemical compounds

Chemical compounds are substances formed by the combination of two or more elements. They are held together by chemical bonds.
Chemical compounds have distinct properties and compositions. The ratio of elements in a compound remains consistent across samples. For instance, ${\text{H}}_2\text{O}$, or water, always has 2 hydrogen atoms bonded with 1 oxygen atom.
It's important to understand the difference between compounds and mixtures. Compounds are chemically bonded whereas mixtures involve physical combinations without chemical bonding. In our exercise, ${\text{MgCl}}_2$ (magnesium chloride) and $\text{MgO}$ (magnesium oxide) form a compound when combined, rather than just a mixture.

Sorrel's cement

Sorrel's cement, also known as magnesium oxychloride (MOC), is a speciality cement. It is made from a mix of magnesium chloride and magnesium oxide.
Sorrel's cement is different from Portland cement. It's lighter and has better resistance against fire.
Below are some features of Sorrel's cement:

• High strength
• Good bonding properties
• Resistance to abrasion
• Environmentally friendly

It is used in industrial flooring, fire-proofing, and in making artificial stones.

Portland cement

Portland cement is the most common type of cement used in construction. It is made by heating limestone and clay in a kiln.
This type of cement is known for its excellent bonding properties and versatility.
Some key components of Portland cement include:

• Calcium silicates
• Alumina
• Iron oxide

Portland cement is essential for making concrete, mortars, and grouts. It's a fundamental material in civil engineering and construction projects.

mixed salt

A mixed salt refers to a chemical compound that contains more than one type of anion or cation. It is a type of chemical compound but more complex than simple salts.
Examples of mixed salts include double salts like ${\text{KAl(SO}}_4{\text{)}}_2{\text{ · 12H}}_2\text{O}$, which is a combination of potassium and aluminum sulfate.
In our exercise, magnesium oxychloride is not a mixed salt since its composition is designed to form a specific compound rather than a random mixture of salts.
The correct answer to the exercise, therefore, highlights a specific chemical interaction rather than a mixed salt solution.