Identify the following examples as either physical or chemical change. (Ill give brainliest if right)

Which of the following elements would you expect to have the lowest ionization energy value? fluorine, lithium, neon, nitrogen

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.

Why does his teacher ask him to balance the equation by including the correct coefficient