Name:____________________________ Block:_________

Solubility Chemistry TermsSolution:

• a mixture of two or more substances

• a mixture of two or more different types of particles that looks

like • ex: salt water, koolaid

Solvent vs SoluteThe is the abundant component of a solution.

The is the component(s) that are abundant

In salt water:

Solvent: water Solute: salt

In KoolAid:

Solvent: water Solutes: sugar, KoolAid crystals

SymbolsThe symbol (aq) after a formula – stands for .This indicates a solution that has as

the ex. NaCl(aq) means “NaCl dissolved in water”

Types of SolutionsSolutions can be:

· liquid – solid

· gas – gas· · liquid – liquid

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Chemistry 11Unit 9 Solution Chemistry

· liquid – gas

· solid – solid

: bronze,steel, brass

What happens when NaCl dissolves?• Water molecules ( ) collide with (solute),

which are in a crystal lattice, knocking Na+ and Cl ions off the crystal and into the water.

• Eventually, the crystal is gone and all the among the water molecules.

Dissociation Equation:

• Because the crystal has been dispersed into , you can no

longer see the salt in the water, and the result is a homogeneous mixture… a solution!

• The ions are surrounded by water molecules (called ) as seen below.

Temperature and Solutions• H makes

the water molecules move faster and collide with the crystal lattice harder and more often

• Thus, a higher temperature .• A higher temperature also

of solute that will dissolve .

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Saturated Solutions• When a solution is , it has the maximum amount of solute possible for a

given amount of solvent

• Saturated solutions have remaining on the bottom

of the container as no more can dissolveTwo processes are occurring in saturated solutions:

These two processes happen at the same rate.

• : NaCl(s) Na+(aq) + Cl(aq)

• : Na+(aq) + Cl(aq) NaCl(s)

These two processes are

opposites, and since they occur

at the same rate results!

Concentration:• The of a solution is the amount of solute in a

given volume of solution

• If there is of solute in a solution, the solution is concentrated.

• If there is a little solute in a solution, the solution is .• The amount of solute is usually measured in grams or moles the volume of solvent is usually

measured in L or mL

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Remember…How many moles of NaCl are needed to make 6.0 L of

a 0.75 M NaCl solution?

Moles = Molarity x Volume

=

=

A is an ionic compound made up of a metal and a nonmetal Salts dissolve in a process called “ ”

This means that the compound not only dissolves, but it 'dissociates' .

• e.g. KCl(s) K+(aq) + Cl(aq)

Every salt dissolves in water to some extent.

The amount of salt required to saturate the solution depends on the type of salt.

Some salts can have a very high molarity before they become saturated, and some become saturated at

very low molarities.

If a salt has a solution concentration greater than 0.1M, it is said to be .If less than 0.1M, it is said to be

Dissociation Equations for SaltsLiF(s)

MgI2(s) (note: 2 iodide ions!)

Na2SO4(s)

2NH4+(aq) + CO3

2-(aq)

Remember: Polyatomic compounds are also ionic in nature!

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Dissociation Equations/Ion Concentrations WORKSHEET Name:________________________

Part 1 - Write dissociation equations for each of the following ionic compounds (salts)

Part 2 - Determine the concentration of each ion in the resulting solution.

Example:

0.50 M SrCl2: SrCl2 (s) Sr2+(aq) + 2 Cl-(aq)

Part 2 0.50 M 0.50 M 1.0 M

1. 0.20 M KBr

2. 0.10 M NaOH

3. 1.5 M ZnSO4

4. 3.0 M CaI2

5. 0.050 M Ba3(PO4)2

6. 1.2 M AgNO3

7. 5.0 M CaCl2

8. 0.40 M Li2CO3

9. 1.5 M Fe(NO3)2

10. 2.0 M Fe2(SO4)3

11. 0.80 M Ca(NO3)2

12. 0.55 M Ag2S

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Covalent CompoundsCovalent molecules have partial charges (if ) or no charges ( )If a covalent compound dissolve in water, it

must be , and it dissolves as a

whole molecule (it doesn't dissociate into ions).

·e.g. Sugar C12H22O11(s) Þ C12H22O11(aq)

Acid Solubility Acids dissolve by to form ions

(see p. 74 HEBDEN for all acids)

Strong partial on O from H2O removes H+ from acid

· E.g. Hydrochloric acid

Chemical Equation:

ASSIGNMENT 5A: Hebden pg 194 #1-4 Pg 210 #28

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What determines Solubility?“ ” Rule

Substances with charges (full or partial) like to mix with one another.

• or ionic solutes tend to in polar solventsCase Study 1: NaCl

• solutes tend to dissolve in non polar solventsCase Study 4: Iodine in Carbon Tetrachloride

dissolves more substances than any other liquid.

The water molecule’s makes it such an excellent solvent.

The polarity allows water to become to many other charged ( ) or

partially charged ( ) molecules. (Case study 2)

Polar vs Non-polar Covalent Bonds

molecules unequally share electrons between atoms, so

have a slight positive charge at one end and a

slight negative charge at the other.

molecules have electrons equally shared between their

atoms.

Water: The Universal SolventWater is a good solvent for many other .

Polar Covalent Molecules include:

• Ammonia NH3 • Glucose C6H12O6 • Urea (NH2)2CO

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*High ratio of O’s and N’s tend to .For example, blood is a water based solution.

Water is also a good solvent for compounds. (a.k.a. salts & electrolytes)

The partial and full each other.

Salts dissociate into their ions in water.

Charged molecules are - from the Greek (hydros) "water" and (philia) "friendship”

- Water loving

- Water - Example: Water & sugar

substances DO NOT carry any kind of charge

Mainly molecules made of C’s and H’s.

Example: Oily or gasoline based substances

This is why…..Oil and Water Don’t Mix

Non-polar, uncharged molecules are • from the Greek (hydros) “water” and (phobia) “fearing” or “hating”

• Water-fearing

• water soluble

• Example: Cholesterol is not water soluble

solvents dissolve non-polar solutes.Examples:

• Turpentine dissolves oil-based paints.

• Cholesterol is important component of greasy cell membranes.

• ASSIGNMENT 5b: Hebden pg 205 #17 Pg 207 #18-22 PG 198#6-8

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ConductivityConductivity is dependent on particles

• solutions conduct very well because charged particles (ions) are present

• solutions conduct very well because are present

• Covalent solutions conduct electricity because no charges are

present (entire neutral molecules are dissolved)

• The more ions in the solution, the the conductivity• Therefore concentrated solutions conduct better than solutions

Solubility & Precipitation

Remember that EVERY salt to some extent in water.

Some salts dissociate a great amount and have a at saturation,

while others become saturated at a very low molarity.

A ' ' salt has a saturation molarity greater than 0.10M, whereas a

'low solubility' salt becomes saturated at a molarity lower than 0.10M.

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The Solubility Table

How to use the Solubility TableUse your table to predict whether the following salts are soluble (S) or low solubility (LS) and whether they

form a precipitate (ppt) in water.

Substance Chemical Formula Soluble? Low Solubility? PPT?

NaOHNH4CH3CO2CaSO4PbCl2KClCaBrK2CO3Al2(SO4)3CuCl2CuCl

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Double Displacement Reactions (revisited)

Let`s suppose you decided to mix equal volumes of two

soluble salt solutions together, such as 0.20M KI(aq) with

0.20M Pb(NO3)2(aq)

KI(aq) is actually K+(aq) and I( aq) Pb(NO3)2 (aq) is actually

Pb2+(aq) and NO3(aq)

By mixing, you`ve introduced and also If either of these combinations are ` ` together, they will be 'oversaturated' and

out of solution (form a solid).

This will be the case for Pb2+ and I and they will form the precipitate thereby

creating a saturated solution of PbI2.

In this case, K+ and NO3- are ‘ , meaning they do not participate

directly in the reaction

Precipitation ReactionsWhen two soluble ionic solutions that have molarities greater than 0.10M are mixed together and at

least one new combination of cation and anion have , a

precipitate forms.

As we know, Pb2+ and I are low solubility together, so when mixed together, they will precipitate

out of solution.

The saturation molarity for PbI2 is 000137M, so solid PbI2 will precipitate out until that molarity remains in

solution as aqueous ions

Practice Question:AgNO3(aq) + NaCl ? + ?

Metals will swap

AgNO3(aq) + NaCl +

Calculate ionic charges to determine chemical formula of products

AgNO3(aq) + NaCl +

Check solubility table to determine if a solid precipitate is formed

AgNO3(aq) + NaCl +

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K2CrO4(aq) + Ba(NO3)2 (aq) → what are the products?

The ions in solution are:

So what (if any) will form a precipitate?

Mixing Ionic SolutionsWhen mixing two ionic solutions three outcomes can result:

• No precipitate forms (all combinations of cation & anion are )• One precipitate forms ( combination of cation & anion have )• Two precipitates form ( combinations of cation and anion have )

Practice QuestionWhat would result if 1.0M solutions of Al2(SO4)3(aq) and Sr(OH)2(aq) were mixed together?

The products would be:

Practice Questions: Separating Ions from Solution WorksheetRemember: Add a cation as a nitrate salt to precipitate an anion. Add an anion as a sodium salt to precipitate a cation.

1. Construct a flowchart to separate solutions that contain one or more of each of the following ions.

a) SO42- and PO4

3-

b) Pb2+ and Ba2+

c) Fe2+, Pb2+, and Mg2+

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d) Br-, CO32-, and SO4

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Using the Solubility Table Worksheet

Using the Solubility Table Worksheet Name: ____________________

Determine the solubility of the following compounds (answers will either be soluble or low solubility):1. HCl

2. CaCl2

3. LiNO3

4. CuCl

5. PbSO4

6. Na3PO4

7. Fe(OH)3

8. (NH4)2S

9. BaBr2

10. H3PO4

11. Hg2Cl2

12. Li2S

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