Chemistry, I need some help

Question

Determine the concentration of a solution prepared by diluting 25.0 micro L of a stock 0.188 M Sr(NO3)2 solution to 150.0 mL

Answer 1

Hello, this is a simple dilution problem: C1V1=C2V2, where C=concentration & V=volume

 

Fill in the blanks:

 

C1V1=C2V2

 

(0.188 M)(25.0 uL)=C2(150X10^3 uL)

 

After converting 150.0 mL to uL, solve for C2 algebraically.

 

C2=3.13x10^-5 M (3 sig. fig.'s)

Answer 2

Justis,

 

To solve this problem, you will use the relationship

 

M_iV_i = M_fV_f

 

where M_i = molarity of the initial solution in mol/L

          M_f = molarity of the final solution in mol/L

          V_i = volume of the initial solution in L

          V_f = volume of the final solution in L

 

Note that in this problem, the initial and final volumes are not given in liters.  First convert to liters and then use those values in the relationship above to solve for M_f.

 

Good luck!!