1. What is a solution? and think

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2 1. What is a solution? and think

3 Solutions

4 Properties of Solutions Solutions: 1. Have no visible parts (particles are small) 2. They are homogeneous evenly distributed particles 3. The particles do not settle out (fall to the bottom & make a layer)

5 Phases solutions can exist in: 1. Solid Solutions: - Alloys: mixtures of metals ex: Brass (Cu + Zn) Steel (Fe + Cr + Ni)

6 Phases solutions can exist in: 2. Liquid Solutions: - Aqueous: made with water ex: NaCl (aq) te.edu/greenbowe/sect ions/projectfolder/flash files/thermochem/solut ionsalt.html

7 Phases solutions can exist in: 3. Gas Solutions: Air (N 2 + O 2 + etc)

8 Measuring Solutions (Qualitatively): Compare the amount of solute to solvent Dilute: Concentrated:

9 Concentration of a Solution

11 and think 1. How can we measure the concentration of a solution?

12 Measuring Solutions Quantitatively): Calculating Concentration Molarity: - Expresses how concentrated a solution is as a number. - Number of moles of solute in a liter of solution. (# of particles in a certain volume)

14 Calculating Concentration: Molarity Practice Problem 1: What is the molarity of a solution containing 1.5 moles in a 500 ml solution?

15 Calculating Concentration: Molarity Practice Problem 2: What is the molarity of a solution formed by mixing 10.0 g of H 2 SO 4 with enough water to make ml of solution?

16 Calculating Concentration: Molarity Practice Problem 3: How many grams of KCl need to be added to make 750 ml of a 0.40 M solution?

17 Calculating Concentration: Molarity Practice Problem 4: What volume is needed to prepare a 3.5 M solution with 3 moles of NaCl?

18 Calculating Concentration: Molarity

19 Calculating Concentration: PPM

20 Calculating Concentration: PPM Parts Per Million: How much is it?

21 Calculating Concentration: PPM Parts Per Million: How much is it? drink/contaminants/index.cfm#list

22 Calculating Concentration: PPM Practice Problem 6: 10 grams of salt is dissolved into 25 kilograms of solution. What is the ppm (parts per million) of the solution?

23 Calculating Concentration: PPM Practice Problem 7: A 60 ppm solution has a total mass of 1.5 kilograms. How much solute needs to be added to create this solution?

24 Calculating Concentration: PPM

25 Calculating Concentration: PPM

26 Calculating Concentration: PPM

27 and think 1. Does the concentration of a solution affect its physical properties?

28 The effect of concentration on the properties of a solution Colligiative Properties of a Solution: The property of a solution that depends upon the concentration of the solute, but not it s identity.

29 Effects of adding a nonvolatile solute to a solution: 1. Boiling Point Elevation: Add a nonvolatile solute, you increase the concentration of the solution, therefore the boiling point of the solution increases. 2. Freezing Point Depression: Add a nonvolatile solute, you increase the concentration of the solution, therefore the freezing point of the solution is lower.

30 Key Idea: The more solute particles, the higher the concentration of the solution, the more the boiling point of the solution increases and the freezing point decreases.

31 Regents Practice Questions:

32 and think 1. Can any amount of a polar or ionic solute dissolve in 100 ml of water?

33 Solubility

34 Solubility Solubility: A measure of how much solute CAN be dissolved in a solvent. There are 3 types of solutions based on solubility: Saturated: (At Equilibrium) The solvent is holding as much solute as it can hold at a particular temp. No more can be dissolved. Points on the line. Unsaturated: Supersaturated:

36 Solubility Solubility: A measure of how much solute CAN be dissolved in a solvent. There are 3 types of solutions based on solubility: Saturated: (At Equilibrium) The solvent is holding as much solute as it can hold at a particular temp. No more can be dissolved. Points on the line. Unsaturated: The solvent is holding less solute than it can hold. More solute could dissolve if added. Points below the line. Supersaturated:

38 Solubility Solubility: A measure of how much solute CAN be dissolved in a solvent. There are 3 types of solutions based on solubility: Saturated: (At Equilibrium) The solvent is holding as much solute as it can hold at a particular temp. No more can be dissolved. Points on the line. Unsaturated: The solvent is holding less solute than it can hold. More solute could dissolve if added. Points below the line. Supersaturated: The solvent is holding more solute than it normally can hold at a particular temp. These solutions are unstable. Points above the line.

Supersaturated Solutions https://www.youtube.com/watch?

40 Supersaturated Solutions v=xsgvy2fpfcw v=qcpidbya_nw =1y3bKIOkcmk

41 Solubility 1. Which substance has the lowest solubility at 10 C? 2. Which substances have the same solubility at 18 C? 3. How many grams of KNO 3 can be dissolved in 100g of water at 65 C?

42 Solubility 4. How many grams of KCl can be dissolved in 200g of water at 60 C? 5. How many grams of KCl can be dissolved in 50 g of water at 60 C? g of KNO 3 in 100g of water at 30 C, would be classified as what type of solution?

43 and think 1. How do you make a solution? 2. What affects the ability to make a solution?

44 H. Factors that affect the solubility of a substance: Nature of the solute Table F to predict solubility in water

45 Like dissolves Like Substances with similar polarities will dissolve in each other: - Polar solutes will dissolve in polar solvents - Ex: HCl will dissolve in water - Non-polar solutes will dissolve in non-polar solvents - Ex: I 2 will dissolve in CCl 4 - Ionic solutes will dissolve in polar solvents - Ex: CaCl 2 will dissolve in water

46 Properties of Solutions Example: Vitamins Water soluble vitamins: C, B 12, B 6 (polar molecules and are eliminated in urine). Fat soluble vitamins: A, E, D, K (non-polar and accumulate in fat)

47 Temperature a). Solids: more soluble as temp increases b). Gases: - high temp = low solubility - low temp = high solubility

48 Pressure Solids: not effected by changes in pressure Gases: - increase pressure = increase in solubility - decrease pressure = decrease in solubility

49 Solutions Dissolving: Process of solute becoming mixed with the solvent (hydration). Ionize/ Dissociation: To break into individual ions Example: NaCl dissolving/ ionizing in water Directions: Draw at leas 3 water molecules around the (+) ion and the (-) ion.

50 Ionizing/Dissociation Animation ons/projectfolder/flashfiles/thermochem/solu tionsalt.html

51 and think 1. What things can affect the RATE of dissolving?

52 Solutions Things that affect the RATE of dissolving: 1. Temperature (move faster with higher temps) 2. Stirring (more contact with solvent) 3. Surface area (more area exposed to contact with solvent)

Regents Chemistry Unit 3C Solutions Text Chapter 13 Reference Tables F, G & T. Chemists have Solutions!

Regents Chemistry Unit 3C Solutions Text Chapter 13 Reference Tables F, G & T Chemists have Solutions! SOLUTIONS homogeneous mixture (uniform composition throughout) Solute - substance being dissolved