The K sp value for strontium fluoride, SrF 2 , is 7.9×10 –10 at 25ºC. Calculate its solubility in g/L.

The KSP value for strontium fluoride, which is s r f 2, is 7.9 times 10 to the negative 10 at 25 degrees Celsius. Here it says to calculate its solubility in grams per liter. Alright. So work I normally see solubility in terms of molarity, which is moles per liter. So what we're gonna have to do here is determine what our molarity is for the compound and then convert it from moles over liters to grams over liters. Strontium fluoride is s r f 2 solid. It breaks them to into our strontium ion plus our 2 fluoride ions. Ksp equals s r 2+timesfminus, the coefficient becomes a power, so that's squared. Here now we can plug in numbers that represent their concentrations. So here this would just be x, and because there's a 2 here, this would be 2 x. So those are the numbers that we plug in for the concentrations. 2 squared is 2 times 2 which is 4, so this is 4 x squared. X times 4x squared is 4x cubed. All right. And they're telling us that the Ksp value is 7.9 times 10 to the negative 10, and that equals the 4x cubed. So just solve for x here. We're gonna divide both sides here by 4. So when I do that, I'm gonna bring it over here, we're gonna see that x x cubed equals 1.975 times 10 to the negative 10. Take the cube root of both sides here. So when I do that, I'm gonna get x equals 5.826 22 5.8236 times 10 to the negative 4 molar. But what exactly does that mean? Well, that means I have 5.8236 times 10 to the negative 4 moles per liter. Because remember molarity is moles per liter. I want the grams per liter. So we're gonna place here on the bottom 1 mole of strontium fluoride and up here the molar mass of strontium fluoride. It's composed of 1 strontium and 2 fluorines. Look on the periodic table and you'll see their masses. Fluorine is 19 grams, strontium is about 87.62 grams. When you combine the masses, you should get total weight of strontium fluoride as 125.62. Moles cancel out and guess what? I'll have grams per liter at the end. So when I do that, I'm gonna get 7.3 times 10 to the negative 2 grams per liter of strontium fluoride compound. So that would be our final answer for this question.