Which of the following is used to denote Sodium Hydroxide in industry?

The term "caustic soda" is commonly used in industry to refer to sodium hydroxide (NaOH). This strong alkaline substance is known for its ability to corrode and dissolve many organic materials, hence the term "caustic." It is widely utilized in various industrial processes, including the manufacturing of soap, paper, and textiles, as well as in water treatment.

In contrast, soda lime is a mixture that typically contains sodium hydroxide along with calcium oxide; it is primarily used for absorbing carbon dioxide in closed environments. Baking soda refers to sodium bicarbonate, a much milder compound used mainly in cooking and baking. Calcium carbonate is a completely different compound used for various purposes, including as a dietary calcium supplement and as a filler in various products. Therefore, "caustic soda" is recognized as the standard industrial term for sodium hydroxide, highlighting its significance in chemical processes.