Answer:
2.1 M
Explanation:
The dilution equation is [tex]M_{s} V_{s} = M_{d} V_{d}[/tex].
[tex]M_{s}[/tex] = the molarity of the sock solution
[tex]V_{s}[/tex] = the volume of the sock solution
[tex]M_{d}[/tex] = the molarity of the diluted solution
[tex]V_{d}[/tex] = the volume of the diluted solution
The stock solution would be what is doing the diluting, so "175 mL of a 3.00 M solution". So [tex]M_{s}[/tex] = 3.00 M. Then: Converting 175 mL to liters: [tex]175 mL * \frac{1 L}{1000mL} = 0.175 L[/tex] (This is [tex]V_{s}[/tex])
And converting 250 mL KCl to liters: [tex]250 mL * \frac{1 L}{1000mL} = 0.250 L[/tex] (This will be [tex]V_{d}[/tex])
Then, we plug in our given into the dilution equation, resulting in:
[tex]3.00 M * 0.175 L = M_{d} * 0.250 L[/tex] (divide both sides by 0.250 L, in order to get [tex]M_{d}[/tex] by itself)
[tex]\frac{3.00 M * 0.175 L}{0.250 L} = M_{d}[/tex]
[tex]M_{d} = 2.1 M[/tex]
So, the molarity of 250 mL KCl made by diluting 175 mL of a 3.0 M solution would be 2.1 M (mol/L).
Hopefully this helped you understand the topic a little bit better. I just finished molarity and dilutions in Chemistry last week. Good luck!
