Question

# Calculate the molarity of each of the following solutions:(a) 30 g of (mathrm{Co}left(mathrm{NO}_{3}right)_{2} cdot 6 mathrm{H}_{2} mathrm{O} ) in ( 4.3 mathrm{L} ) of solution (b) ( 30 mathrm{mL} ) of ( 0.5 mathrm{M} mathrm{H}_{2} mathrm{SO}_{4} ) diluted to ( 500 mathrm{mL} )

Solution

Molar mass ef ( C_{0}left(N O_{3}right)_{2} cdot G H_{2} O=7424 )

[

text { Molarity }=frac{30}{7424} times frac{1}{4.3}=9.4 times 10^{-4}

]

(b) molarmass of ( mathrm{H}_{2} mathrm{SO}_{4}=98 )

NLOw, ( 30 mathrm{ml} ) ef ( 0.5 mathrm{MH}_{2} mathrm{SO}_{4} )

( =3 phi times frac{0.5}{1000} )

mole

[

=1.5 times 10^{-2} text {mole }

]

Then, mularity ( =frac{1 cdot 5 times 10^{-2} times 10^{3}}{550} times 10^{3} )

[

begin{array}{l}

=frac{15}{500}=frac{3}{100}=frac{0.03 pi}{108}=

+108

end{array}

]