Dilutions

• When two solutions are mixed the concentration changes
• Dilutions- the process of decreasing the concentration by adding a solvent (usually water)
• The amount of solute does not change
  n1=n2 (number of moles before= number of moles after)
• Because concentration is mol/L we can write C= n/V , n=CV, C1V1=C2V2

Determine the concentration when 100 mL of 0.1M HCl is diluted to a final volume of 400 mL

C1V1=C2V2

V1= 100 mL
C1= 0.10 M

V2= 400 mL

0.10 M X 100 mL= C1 X 400 mL

C1= 0.26 M

(100)(0.10)/400 = 0.025 M= C2

How much water must be added to 10.0 m: of 10.0 M Na2SO4 to give a solution with a concentration of 0.50 M? 

V1= 10 mL

C1=10.0 M

C2= 0.50 M

V2= 200 mL

(10.0)(10.0)/0.50= 200mL

ΔV= 200-10.0= 190 mL

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BY KRYSTA DEL ROSARIO :)