Question

Caustic soda is a common name for:
A. $Mg{\left( {OH} \right)_2}$
B. $KOH$
C. $Ca{\left( {OH} \right)_2}$
D. $NaOH$

Answer 1

We know that caustic Soda is a common name for$\;NaOH$ (Sodium Hydroxide). It is known as caustic because of its property to corrode or break down any chemical compound when exposed through the chemical reactions.

Complete step by step answer:
Caustic soda or$\;NaOH$is an inorganic chemical compound which is also known as lye. It is ionic in its chemical nature. In reactions, $\;NaOH$ breaks down in $N{a^ + }$ and $O{H^ - }$ and participates further in reactions. Caustic soda is the hydrated form of $\;NaOH$ due to absorption of moisture from the environment. Naturally, it is found in white coloured waxy solid which is widely used for making candles and soaps.
$Mg{\left( {OH} \right)_2}$or magnesium hydroxide is a chemical compound used to treat stomach acidity, heartburn and sometimes constipation too. It is categorized in a group of medicines called saline laxatives which retain water in the intestine thus increasing bowel movements.
$\;KOH$ potassium hydroxide is also known as Caustic Potash or potash lye. It is a powerful base and highly corrosive.
$Ca{\left( {OH} \right)_2}$ or calcium hydroxide is also commonly known as caustic lime. It is commonly insoluble in water and gives water a milky appearance. On dissolution with water, it is also known as limewater.

Hence, the correct answer is D.

Note: We know that sodium hydroxide $\;NaOH$ is a strong base and alkali which is used for protein denature or digest proteins at room temperature. This compound readily dissolves in water and can absorb moisture and $C{O_2}$ from the environment. $\;NaOH$ form a series of hydrates as $\;NaOH.n{H_2}O$ and most commonly monohydrate is found in the environment. It does not dissolve in alcohol ether and non-polar solvents and has wide applications in many industries like pulp, paper, soap and detergent industry. On reaction with acids, they form salts and water. This property is used widely in many chemical reactions. E.g., $NaOH(aq) + HCl(aq) \to NaCl(aq) + {H_2}O(l)$