Question 10

B is the false statement about dissociation.

Dissociation is a process where compounds, typically ionic, break apart into their constituent ions in a solution. Therefore, the statement that "ions are not present" is false, as dissociation specifically involves the formation of ions.

A) It is reversible.

This statement is true because dissociation can often be reversed, allowing the ions to recombine to form the original compound under certain conditions. Many dissociation processes, especially in solutions, are dynamic and can reach equilibrium.

B) Ions are not present.

This statement is false because the very definition of dissociation involves the separation of a compound into its ions. When a substance dissociates, the presence of ions in the solution is a fundamental characteristic of the process.

C) It involves molecules separating.

This statement is accurate as dissociation indeed involves the separation of molecules into individual ions. This process is essential in understanding how ionic compounds behave in solvents, such as water.

D) None of the above.

This statement is incorrect because option B is a false statement regarding dissociation. Therefore, it cannot be the case that none of the statements are false.

Conclusion

The false statement about dissociation is that "ions are not present," as dissociation fundamentally involves the creation of ions from a compound. Options A and C correctly describe aspects of dissociation, while D incorrectly asserts that all statements are true. Thus, option B is definitively the correct choice as the false statement.