Question

the generic double displacement reactions is ab + cd ---> ad + cb
the a and the c are cations. the b and d are anions
the reaction will never form ---> ac + bd
why not?

○ i think of another fake answer so you know this isnt it.
○ not true. it can happen.,
○ cations will not combine with another cation.

Explanation:

In double displacement reactions, cations (positively charged ions like A and C) and anions (negatively charged ions like B and D) combine based on charge attraction. A cation (A or C) must combine with an anion (B or D), not another cation. The product AC would require two cations (A and C) to bond, which is impossible because like charges repel and ionic bonds need opposite charges. So the reaction can’t form AC + BD as A and C are both cations and won’t combine. The first option is a fake answer, the second is incorrect (it can’t happen), and the third option correctly explains the charge - based reason.

Answer:

C. Cations will not combine with another cation.