What is the checmical symbol for Thorium^+2?

I'm confused with ^+2

Estructura 7.2 completar repaso 1 - ¿lógico o ilógico? 1 - ¿lógico o ilógico? listen and indicate whether each question and response is lógico or ilógico.

An aqueous solution of calcium hydroxide is standardized by titration with a 0.120 m solution of hydrobromic acid. if 16.5 ml of base are required to neutralize 27.5 ml of the acid, what is the molarity of the calcium hydroxide solution?

Atank contains 240 liters of fluid in which 10 grams of salt is dissolved. brine containing 1 gram of salt per liter is then pumped into the tank at a rate of 6 l/min; the well-mixed solution is pumped out at the same rate. find the number a(t) of grams of salt in the tank at time t.