If we begin the problem with 120. grams of
N
a
2
O
and we are trying to find the mass of
N
a
O
H
that can be produced, this is a gams to grams
g
r
a
m
s
→
m
o
l
s
→
m
o
l
s
→
g
r
a
m
s
120
.
g
N
a
2
O
x
1
m
o
l
N
a
2
O
62
.
g
N
a
2
O
x
2
m
o
l
N
a
O
H
1
m
o
l
N
a
2
O
x
40
.
g
N
a
O
H
1
m
o
l
N
a
O
H
=
the gfm of
N
a
2
O
is (2 x 23 + 1 x 16 = 62)
the gfm of
N
a
O
H
is (1 x 23 + 1 x 16 + 1 x 1 = 40)
The mole ratio from the balanced chemical equation is 2 moles of
N
a
O
H
for every mole mole of
N
a
2
O
.