Question

Question #a4cd9

Answer 1

No ppt forms ... `K_"sp" (=2.4 x 10^-5)` > `Q_"sp"(1.6x10^-5)`

Explanation:

`20ml(0.01MCaCl_2) + 20ml(0.008MNa_2SO_4)`
=> `(0.02)(0.01)"mole" CaCl_2` + `(0.02)(0.008)"mole" Na_2SO_4`
=> `0.0002"mole" CaCl_2` + `0.00016"mole"Na_2SO_4`

=> `Na_2SO_4` is the limiting reagent => `1.6x10^-4"` mole `CaSO_4`

`[CaSO_4]` = `1.6x10^-4"` `"mole" CaSO_4` / `"0.040L Solution"` = `0.004M`

0.004M`CaSO_4 rightleftharpoons` +0.004M`(Ca^(+2))` + 0.004M`(SO_4^(2-))`

`Q_(sp) = [Ca^(+3)][SO_4^(2-)] = (0.004M)(0.004M)` = `1.6x10^-5`

`K_(sp)=2.4x10^-5 > Q_(sp) = 1.6x10^-5` => No Ppt will form.