Question

Which of the following is not a base?
A. $NaOH$
B. $KOH$
C. $N{H_4}OH$
D. ${C_2}{H_5}OH$

Answer 1

Hint: In this question we are discussing about the bases (Base is a substance which dissociates in aqueous solution to form hydroxide $O{H^ - }$).

Complete step by step answer:
-$NaOH$ (Sodium Hydroxide): NaOH is a strong base (A strong base is a base which dissociates completely in aqueous solution. These compounds ionize in water to yield one or more hydroxide ion per molecule base)
 -The pH (potenz of hydrogen) value of sodium hydroxide is 13.
 So, Option (A) is Incorrect
- $KOH$ ( Potassium Hydroxide ): KOH is a strong base . It is completely ionized in the aqueous solution .
 The pH (Potenz of Hydrogen) value of KOH is 13.5
 So, Option (B) is Incorrect.
 -$N{H_4}OH$ ( Ammonium Hydroxide): Ammonium hydroxide is a weak base ( A weak base is a base which is not completely dissociated into aqueous solution) .
 The pH( Potenz of Hydrogen) value of ammonium hydroxide is 11.6
 So, Option (C) is Incorrect.
- ${C_2}{H_5}OH$ ( Ethanol): Ethanol is not a base , but it is volatile solvent.
 Ethanol is a very polar molecule due to its hydroxyl ($O{H^ - }$) group, with the high electronegativity of oxygen allowing hydrogen bonding to take place with other molecules.
 So , Option (D) is Correct
So, the correct answer is “Option A”.

Additional Information: Ethanol is a natural by-product of plant fermentation and also can be produced through the hydration of ethylene.

Note: Ethanol is highly flammable and should not be used near open flames. Ethanol inhalation can cause coughing or headaches. Ethanol is a common ingredient in many cosmetics and beauty products. It acts as an astringent to help clean skin, as a preservative in lotions and to help ensure that lotion ingredients do not separate, and it helps hairspray adhere to hair.