Question

Which of the following is soluble in water?

• A. ${\mathrm{CS}}_2$
• B. ${\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}$
• C. ${\mathrm{CCl}}_4$
• D. ${\mathrm{CHCl}}_3$

Answer 1

The correct option is B

${\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}$

Explanation for correct option:

B. ${\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}$

• Water is a polar solvent with hydrogen bonding, ethyl alcohol molecules should have polarity or H-bond in order to dissolve in water.
• Ethyl alcohol possesses hydrogen bonding as well as being polar due to the strong electronegativity of oxygen; as a result, it is water-soluble.

Explanation for incorrect options:

A. ${\mathrm{CS}}_2$

• ${\mathrm{CS}}_2$ is non-polar.
• It won't dissolve in water.

C. ${\mathrm{CCl}}_4$

• ${\mathrm{CCl}}_4$ is non-polar in the third scenario. Any bond dipoles$(\mathrm{C}-\mathrm{Cl})$ will cancel out because of the molecule's tetrahedral symmetry.
• It will be water-insoluble.

D. ${\mathrm{CHCl}}_3$

• Chloroform is a moderately polar chemical.
• However, it is unable to form any strong bonds (such as hydrogen bonds) with water.
• Its solubility in water is quite low due to the lack of a strong contact with water.

Hence, the correct option is B i.e. ${\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}$.