91影视

We first need to identify the acidic or basic behavior of each compound. For this, we look at their chemical formulas and the ions they dissociate into when in solution. (a) BaCl鈧� -> Ba虏鈦� + 2Cl鈦� This compound dissociates into a barium ion (Ba虏鈦�) and two chloride ions (Cl鈦�). Neither of these ions are acidic or basic, so BaCl鈧� is a neutral salt. (b) LiCl -> Li鈦� + Cl鈦� This compound dissociates into a lithium ion (Li鈦�) and a chloride ion (Cl鈦�). Neither of these ions are acidic or basic, so LiCl is a neutral salt. (c) KCl -> K鈦� + Cl鈦� This compound dissociates into a potassium ion (K鈦�) and a chloride ion (Cl鈦�). Neither of these ions are acidic or basic, so KCl is a neutral salt. (d) TiCl鈧� -> Ti鈦粹伜 + 4Cl鈦� This compound dissociates into a titanium ion (Ti鈦粹伜) and four chloride ions (Cl鈦�). The titanium ion has a strong charge of +4 and can undergo hydrolysis to produce H鈦� ions in solution, making this compound acidic. Ti鈦粹伜 + 4H鈧侽 -> Ti(OH)鈧� + 4H鈦�

Now that we have identified the acidic or basic behavior of each compound, we can compare their pH values. The neutral salts (BaCl鈧�, LiCl, and KCl) will have a pH of 7, as they do not produce H鈦� or OH鈦� ions in the solution. However, the TiCl鈧� compound is acidic and will have a pH lower than 7, as it produces H鈦� ions in the solution through the hydrolysis reaction of Ti鈦粹伜 ions.

Since TiCl鈧� is the only compound that produces H鈦� ions in the solution and has a pH lower than 7, it is the compound with the lowest pH among the given options. So the answer is (d) TiCl鈧�.