600 g CaCl
2
would be required to make
2 L
of a
3.5 M
solution.
Step-by-step explanation:
Molarity
=
moles of solute
liters of solution
A
3.5 M CaCl
2
solution contains
3.5 moles
CaCl
2
/L solution
.
We need to convert moles
CaCl
2
to grams. We do this by multiplying moles
CaCl
2
by its molar mass
(
110.978 g/mol
)
.
3.5
mol CaCl
2
×
110.978
g CaCl
2
1
mol CaCl
2
=
300 g CaCl
2
rounded to two significant figures
Since
300 g CaCl
2
are needed to make
1 L
of a
3.5 M
solution,
600 g CaCl
2
are needed to make
2 L
of a
3.5 M
solution.