Which species contain a dative covalent bond?

I.     HCHO

II.     CO

III.     \({{\text{H}}_{\text{3}}}{{\text{O}}^ + }\)

A.     I and II only

B.     I and III only

C.     II and III only

D.     I, II and III

C

This question asked which species contain a dative covalent bond from a list of three. One respondent stated that the term coordinate bond is often used, which is correct. However, in the guide in the teachers note corresponding to AS 4.2.2, the term that is used is dative covalent; hence candidates should be familiar with this term when used in questions. 40% of candidates gave the correct answer to this question.