Answer to Question #95651 in General Chemistry for Raylene Hammond

Question

A 5.09 g mixture contains both lithium fluoride, LiF, and potassium fluoride, KF. If the mixture contains 3.03 g fluorine, what is the mass of the KF in the mixture?

Answer 1

Let us consider the mixture contain same amount of lithium and potassium

Total amount of mixture 5.09g

Amount of flourine their 3.03g

So amount of potassium and lithium in the mixture 2.06g molecular weight of potassium 39 and for

Lithium 7. So 46gm of Li and K mixture contain 39gm of K. Therefore 2.06 gm of mixture contain 1.746 gm of K. Now quantity of F in case of KF is actually half of the total amount of F i.e. 1.515gm. Therefore the amount of KF is 3.261gm