Given :
Initial volume , [tex]v_1=50\ ml[/tex] .
Final volume , [tex]v_2=300 \ ml[/tex] .
Initial molarity , [tex]M_1=0.45 \ M[/tex] .
To Find :
Molarity of 300 ml solution .
Solution :
We know , for constant moles .
[tex]M_1v_1=M_2v_2\\\\M_2=\dfrac{M_1v_1}{v_2}\\\\M_2=\dfrac{50\times 0.45}{300}\ M\\\\M_2=0.075\ M[/tex]
Therefore , the molarity of the resulting solution is 0.075 M.
Hence , this is the required solution .