Question #bfaae

1 Answer
Mar 2, 2017

a) 1.4103 M F
b) 1.141013g KF

Explanation:

Molarity is the number of moles per liter of solution. The molecular (atomic) weight of fluorine is 19g/mol, or 19000 mg/mol. 1.4mg F is 1.4103g. Therefore, its molarity is 1.4103 M in this case.

To reach a 1.4103 M concentration of F in 1.4×108 L requires
1.4×108 L * 1.4103 mol/L = 1.961011 mol F
Delivered as KF, we would need the same number of moles of KF. Adding “K” to the “F” weight previously used, we have a molecular weight of 58g/mol. The amount of grams of KF that will need to be added is then
1.961011 mol * 58g/mol = 113.71011g , or 1.141013g KF