Understanding Quick Lime

The question asks for the common name "Quick lime". We need to identify which chemical compound is also known by this name from the given options.

Quick lime is a commonly used term in chemistry and industry. It refers to a specific chemical substance.

Let's look at the options provided:

• Calcium oxide
• Potassium hydroxide
• Potassium carbonate
• Calcium sulphate

We need to determine which of these compounds is synonymous with Quick lime.

Quick lime is the common name for Calcium oxide. Its chemical formula is $\text{CaO}$. It is a white, caustic, alkaline, crystalline solid at room temperature. It is widely used in many applications, including steel making, lime production, water treatment, and as a drying agent.

Let's briefly consider the other options:

• Potassium hydroxide ($\text{KOH}$): This is commonly known as Caustic potash.
• Potassium carbonate ($\text{K}_2\text{CO}_3$): This is a salt and is also known as Potash.
• Calcium sulphate ($\text{CaSO}_4$): This compound is found in various forms, including Gypsum ($\text{CaSO}_4 \cdot 2\text{H}_2\text{O}$) and Plaster of Paris ($\text{CaSO}_4 \cdot \frac{1}{2}\text{H}_2\text{O}$). It is not Quick lime.

Based on chemical nomenclature and common names, Calcium oxide is indeed known as Quick lime.

Therefore, ____________ is also known as Quick lime.

The correct answer is Calcium oxide.