How will you convert benzaldehyde into the following compounds?
(i) benzophenone (ii) benzoic acid (iii) 2-hydroxyphenylaceticacid.

Explanation

`{:(underset(("Benzaldehyde"))(C_(6)H_(5)CHO) underset((O))overset(OH^(ө)//KMnO_(4))rarr underset(("Benzoic acid"))(C_(6)H_(5)COOH)),(" "darr underset(Delta)(NaOH//CaO)),(underset(("Benzophenone"))(HCl + C_(6)H_(5) - COC_(6)H_(5)) underset(underset("Benzoylation")("Anhydrous" AlCl_(3)))overset(C_(6)H_(5)COCl)rarr underset(("Benzene"))(C_(6)H_(6))):}`
(ii) Conversion of benzaldehyde into benzoic acid:
`underset(("Benzaldehyde"))(C_(6)H_(5)CHO) underset((O))overset(OH^(ө)//KMnO_(4))rarr underset(("Benzoic acid"))(C_(6)H_(5)COOH)`
(iii) conversion of benzaldehyde into 2-hydroxy phenyl acetic acid:
`underset(("Benzaldehyde"))(C_(6)H_(5)CHO) overset(HCN)rarr underset(("Phenyl Cyanohydrin"))(C_(6)H_(5) - underset(underset(OH)(|))overset(overset(H)(|))(C) - CN) underset("excess")overset(H^(+)//H_(2)O)rarr underset(("2-hydroxy phenyl acetic acid"))(C_(6)H_(5) - underset(underset(OH)(|))overset(overset(H)(|))(C) - COOH)`