What is the mass of 0.25 mole of silvertrioxonitrate5

What does x represent in the formula for the compound xcl4?

Using a value of ksp = 1.8 x 10-2 for the reaction pbcl2 pb+2(aq) + 2cl -(aq). if the value of ksp was determined to be only 1.2 x 10-2: too much solid has dissolved. additional precipitate is forming. the solution is unsaturated. the ions are now combining to reduce their concentrations.

The boiling point of liquids is very high what does it indicate