How do you balance #Na + MgF_2 -> NaF + Mg#?

1 Answer
Dec 7, 2015

Answer:

#2Na+MgF_2 rarr 2NaF + Mg#

Explanation:

The #2# F's on the left side (#MgF_color(red)(2)#) imply the that right side must have #2# F's (or a multiple of #2#).

The only F on the right side is in NaF
so to have #2# F's on the right side we will need #2# NaF's.
#color(white)("XXX")color(red)(2NaF)+Mg#

This gives us #2# Na's on the right side (#color(blue)(2Na)F#)
which implies we will need #2# Na's on the left side.
#color(white)("XXX")color(blue)(2)Na + MgF_2rarr color(blue)(2Na)F + Mg#

At this point the transformation becomes balanced:
On both sides we have:

#2 Na#'s
#1 Mg#, and
#2 F#'s