Tag: organic compounds with functional group containing oxygen (part-1)

Questions Related to organic compounds with functional group containing oxygen (part-1)

The major product of Raschig process was taken for litmus test.It was observed that it turned:

  1. red litmus blue

  2. blue litmus red

  3. no change in colour

  4. very slight change in colour from red towards blue


Correct Option: B
Explanation:

Phenol is obtained as the major product of Raschig process.Phenol is mildly acidic in nature so it turns blue litmus red.

Phenol is a:

  1. volatile liquid

  2. non-volatile liquid

  3. volatile solid

  4. non-volatile solid


Correct Option: C
Explanation:

Phenol is a non-volatile solid. its boiling point is 182 deg C which is high due to intermolecular hydrogen bonding.

Alcohols containing only up to ___________ carbon atoms are completely miscible with water.

  1. three

  2. four

  3. five

  4. two


Correct Option: A
Explanation:

Hydroxyl group makes the alcohol molecule polar and these are used as protic solvents. Two opposing solubility trends in alcohols are the tendency of the polar OH to promote solubility in water and the tendency of the carbon chain to resist it. So, methanol, ethanol, propanol are miscible in water as the OH group overcomes the short carbon chain.

Among the following compounds, the most acidic is:

  1. p-nitrophenol

  2. o-hydroxybenzoic acid

  3. p-toluic acid

  4. p-hydroxybenzoic acid


Correct Option: B
Explanation:

Order of strength is ortho hydroxy benzoic acid > Toulic acid > p-hydroxy benzoic acid > p nitro phenol. Ortho hydroxy acid is strongest acid due to stabilisation conjugate by intermolecular H-bond which outweigh the electron donating resonance effect of –OH

 

In which of the following solvents, KI has highest solubility? The dielectric constant $(\epsilon)$ of each liquid is given in parentheses.

  1. $ C _{6}H _{6}(\epsilon =0)$

  2. $(CH _{3}) _{2}CO(\epsilon =21)$

  3. $CH _{3}OH(\epsilon =32)$

  4. $CCl _{4}(\epsilon =0)$


Correct Option: C
Explanation:

KI is an ionic compound. Hence, it will be most soluble in apolar solvent, which has a high value of dielectric constant. Hence, $CH _3OH$ with the highest value of dielectric constant among the given options will provide high solubility.

Phenol is an organic compound even though it is soluble in water due to the presence of:

  1. ionic bonding

  2. covalent bonding

  3. hydrogen bonding

  4. coordinate bonding


Correct Option: C
Explanation:

Phenol is an organic compound even though it is soluble in water due to the presence of hydrogen bonding. Phenol has hydroxyl group which is involved in the formation of hydrogen bonds with water. It increases the solubility.  Hydrogen bonding is possible when $H$ atom is attached to electronegative $N,\ O$ or $F$ atom.