How do I find the concentration of NaCl when given ...

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[poiuyt]

I know c = n/V
but I don't know how to get there with the given information:

Balanced equation: NaCl + AgNO3 --> NaNO3 + AgCl
- 30mL of NaCl is mixed with 30mL of AgNO3
- AgNO3 has a molarity of 0.40

thanks in advance!

[Otis]

"I know c = n/V", I take that to mean "concentration ( in molarity) equals moles per liter.

So, you need to solve for the molarity of the NaCl solution.

One method might be to determine the moles of AgNO₃ in 30.0 ml of a 0.40 M soln. using M x Vol = moles

0.40 M x 0.030 L = 0.012 mole AgNO₃

Since the balanced equations shows a 1:1 ratio of AgNO₃ to NaCl, 0.012 mole of NaCl reacted.

Now, moles divide my volume (in L) will give us the concentration in molarity

0.012 mole NaCl / 0.030 L = 0.40 M NaCl

Hope this helps plan your next problem solving.

Otis