I'm doing the single replacement reaction Mg +FeF3. Would it yield MgF3+Fe? What about the single replacement reaction Li+K2SO4? Would that yield LiSO4+K2? Thanks for checking.

Answer 1

You have to balance the charges of the ions in the compound.

Fluorine has a charge of -1, so when magnesium replaces the iron (III), the new compound is MgF2. Now all that is left to do is balance the reaction.

The sulfate group has a charge of -2, meaning lithium sulfate is Li2SO4. Potassium doesn't exist as a diatomic, so the actual reaction is:

Li + K2SO4 yields Li2SO4 + K

Also balance the above reaction.

Hope this helps.