You add 30.00 mL of a 0.30 M solution to a 100 mL volumetric flask and then fill the flask with water to the 100 mL mark. What is the resulting concentration of hydrobromic acid in molarity?
Please show the steps so I know how to do it, thank you!
Alex
Molarity (M) = moles/liters
If you have 30.00mL of 0.30 M of HBr (Hydrobromic acid) you can solve for moles by rearranging the above equation:
first, convert 30.00 mL to Liters: 30.00 mL/1000 = .0300 L
then: moles = Molarity * liters so moles = .30 M * .0300 L = .009 moles HBr
then using the same equation you can find the resulting molarity using the total volume of the solution (total volume of solution is 100 mL because you fill the flask to the 100 mL line)
first, convert 100 mL to liters
100 mL / 1000 = .100 liters
then, plug in to the molarity equation
M = mols/liter
M = .009 mol HBr / .100 liters
M = 0.09 M
The resulting concentration of hydrobromic acid in molarity is 0.09 M