Concentration and Dilution

Question 1

1. A solution
2. A solution is made up of (definitions)

Answer 1

1. A homogeneous mixture that cannot be distinguished under a magnifying instrument
2. Solute: substance that is being dissolved
3. Solvent: Substance that does the dissolving

• There is always more solvent than solute

Question 2

Aqueous solution

Answer 2

Solvent is water

Question 3

Properties of a solution amd three important properites

Answer 3

• A solution’s properties are what distinguish it from other solutions

1. Solubility
2. Concentration
3. Electrical Conductivity

Question 4

Solubility (of a solute)

Answer 4

• Maximum amount of solute that can be dissolved in a given amount of solvent. The units are the same as concentration (g/L)

Question 5

Concentration in g/L

Answer 5

• quantity or amount of dissolved solute in a given amount of solution
• C=m/v
• M=c*v
• V=m/c

Question 6

Concentration in % m/v

Formulas and units

Answer 6

Units: concentration is %m/v,

mass: grams
volume: ml

Formulas:

c=m/v *100%

m=c*v/100

v=m/c*100%

• Volume has to be in ml

Question 7

Concentration in ppm

1. Definition
2. 1 ppm means
3. Units
4. Formula

Answer 7

1. When the amount of solute is very small, the concentration can be expressed in “parts per million” the number of parts of solute in a million parts of a solution
2. 1 gram of solute in a million g of a solution or 1g of solute per one million Liters of a solution
3. c=ppm, m=mg, v=L
4. c=m/v , m=c*v, v=m/c

Question 8

Converting units of concentration

1. 1 g/L into ppm
2. ppm into g/L
3. 1% m/v into ppm
4. ppm into %m/v
5. g/L into g/mL
6. g/mL into g/L
7. g/L into % m/v
8. % m/v into g/L
9. % m/v into g/mL
10. g/ml=%m/v

Answer 8

1. *1000=ppm
2. /1000=g/L
3. *10000=ppm
4. /10000=%m\v
5. /1000=g/mL
6. *1000=g/L
7. /10=%m\v
8. *10=g*L
9. /100=g/L
10. *100=%m/v

Question 9

Dilution:

Answer 9

• A laboratory technique that is used to decrease the concentration of a solution by adding a solvent (typically water), The quantity of a solute does not change because we are only adding solvent.
• production f medication,beverages…

adding too much water in a baby formula can cause problems (seizures,nausea,diarrhea…)

• not enough water=thirst,weight gain,kidney problems

Question 10

1. Dilution formula
2. V2=

Answer 10

1. C1V1=C2V2
2. V2=V1+water added
3. g/L and L