[JamesIon]

If 10.0 mL of water is added to 5.0 mL of 0.50 M SbCl3, what is the new molarity?

This is how the book did it..


0.0050 L x 0.50 mol/L = 0.0150 L x ? M

0.0025 mol/ 0.0150 L = 0.17 M


Question is... where did that 0.0150 L come from? I know where 0.0025 moles is from but I have a problem figuring out were 0.0150 L came from.

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We're basically trying to find the morality by diluting SbCl3. During the process we added 4mL of H2O, now we need to find the Molarity. I tried using this example above to figure out my Molarity, but it doesn't make sense.

[Sophia7X]

Since the water is poured into the SbCl3 solution, the total volume increases. 10.0 mL + 5.0 mL = 15 mL (0.0150 L)

[JamesIon]

Since the water is poured into the SbCl3 solution, the total volume increases. 10.0 mL + 5.0 mL = 15 mL (0.0150 L)

What happens when you add 2mL of 6M HCl instead into the calculation. How would you find the Molarity from that?

Would the first thing be to calculate the moles of the HCl solution,

mols HCl = 2mL x 6M = 12 mols

Then add the mols of SbCl3 and HCl, then divide by 0.007 L to find molarity of SbCl3?

V = 5.0 mL + 2.0 mL = 7.0 mL

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The book mentions : Recognize that when 6 M HCl is added to the diluted solution of SbCl3 in HCl that the moles of H+ and Cl- must be combined before dividing by the total volume. Then again, that might be not needed and only needed when fining the molarity of H+ and Cl-.