precipitation

Green precipitates, white does not

NO₃-

C₂H₃O₂

-ClO-

ClO₄

-Cl

-

_SO

42-

OH

-

CO

32-

PO

43- CrO4

2-Group 1: Na+_,K+_,

NH₄+

Group 2: Mg2+_,

Ca2+_,Ba2+

Transition metal cations, Pb2+_{, Hg}

22+

Mg(OH)₂ BaSO₄

AgCl PbCl₂ Hg₂Cl₂

The super fun precipitation naming game that is really fun. Make this table. Name each ion. Put the name in the box.

Na+ K+ NH₄+ Mg2+ Ca2+ _Ba2+ _Ag+ _Pb2+

Hg₂2+ _NO

3- ClO- Cl- SO42- OH- CO32- PO4

3-Na+ K+ NH₄+ Mg2+ Ca2+ _Ba2+ _Ag+ _Pb2+

Hg₂2+ _NO

3-Now cut up the paper so you have fun little squares with stuff On them. Notice how much fun you are having.

Na+ K+ NH₄+ Mg2+ Ca2+ _Ba2+ _Ag+ _Pb2+

Hg₂2+ _NO

3- ClO- Cl- SO42- OH- CO32- PO4

3-Na+ K+ NH₄+ Mg2+ Ca2+ _Ba2+ _Ag+ _Pb2+

Hg₂2+ _NO

3-Land on a white square, write the ions

Land on a green square, John Travolta and name the compound

Na+ K+ NH₄+ Mg2+ Ca2+ _Ba2+ _Ag+ _Pb2+

Hg₂2+ _NO

3-Na+

1

K+

2

NH₄+ 3 Mg2+ 4 Ca2+ 5 Ba2+ 6 Ag+ 7 Pb2+ 8 Ba2+ 9 Mg2+ 10 Ag+ 11 K+ 12 Pb2+ 13 Ca2+ 14

Hg22+

15

SO₄2- _NO

3- ClO- Cl- SO42- OH- CO32- PO₄3- SO₄2- NO₃- OH- PO₄3- Cl- CO32- Cl

Put the fun pieces of paper into the fun newspaper box. Get a Blank piece of paper and call it the “super fun score sheet for the Super fun precipitation naming game”.

Rules.

One group member picks a fun piece of paper. Another group member picks another one.

1)  Two cations (+ and +). Write “dud” on the scoresheet 2)  Two anions (- and -). Write “dud” on the scoresheet. 3)  A cation and an anion (+ and -). Put the cation next to

the anion. If you land on a white square write, for

example, Na+ (aq) Cl-_{(aq) on the scoresheet. If you land}

on a GREEN SQUARE…. Do John Travolta and write, for example MgCl₂(s) AND name the

compound, magnesium chloride.

4)  First one to 100 compounds wins a prize. (if they are

Green precipitates, white does not

NO

₃-

_Cl

-

_SO

42-

OH

-

CO

32-

PO

43- CrO4

2-Group 1: Na+_,K+_,

NH₄+

Group 2: Mg2+_,

Ca2+_,Ba2+

Transition metal cations Mg(OH)₂ BaSO₄ AgCl

name

formula precipitate

name

1)Silver nitrate Potassium carbonate 2)Ammonium carbonate Cobalt(III) chloride 3)Sodium phosphate Barium hydroxide 4)Silver acetate Sodium chloride 5) Copper(II)sulfate Sodium chromate 6)Nickel (II) acetate Potassium phosphate 7)Ammonium chromate barium chloride

8) Sodium hydroxide Mercury (II) nitrate

9) Potassium phosphate Barium nitrate

Table 4.4

NH₄+_ammonium

NO₂-_nitrite

NO₃-_nitrate

SO₃2-_sulfite

SO₄2-_sulfate

HSO₄-_bisulfate

OH-_hydroxide

CN-_cyanide

PO₄3-_phosphate

HPO₄2-_{hydrogen phosphate}

H₂PO₄-_{dihydrogen phosphate}

CO₃2-_carbonate

HCO₃-_bicarbonate

ClO-_hypochlorite

ClO₂-_chlorite

ClO₃-_chlorate

ClO₄-_perchlorate

C₂H₃O₂-_acetate

MnO₄-_permanganate

Cr₂O₇2-_dichromate

CrO₄2-_chromate

O₂2-_peroxide

These are the charges you need to know

G1 G2 G3 G6 G7

+1 +2 +3 -2 -1

Na+ _Mg2+ _Al3+ _O2- _F1-

K+ _Ca2+ _S2- _Cl1- _Ba2+

You only “need to know” the Polyatomic ions that are listed In your super green precipitation table

Fe(NO

₃

)

₃

(s)

Fe(NO

₃

)

₃

(s)

-3

Fe(NO

₃

)

₃

(s)

-3

+3

Fe

3+

_(aq)+3NO

Co

₃

(PO

₄

)

₂

(s)

Co

₃

(PO

₄

)

₂

(s)

-6

+6

Ca

₃

(PO

₄

)

₂

(s)

-6

+6

3

X

2

=+6

3Co

2

_{+(aq)+2 PO}

What ions are produced?

BaCl₂(s)⎯ →⎯ Ba2+(aq) + Cl₂−(aq)

BaCl₂(s)⎯ →⎯ Ba2+(aq) + Cl 2−(aq)

BaCl₂(s)⎯ →⎯ Ba2+(aq) + 2Cl−(aq)

Fe NO

(

₃

)

₃(s) ⎯ →⎯ Fe3+(aq)+ NO₆−(aq)

Fe NO

(

₃

)3

(s) ⎯ →⎯ Fe3+(aq)+

(

NO₃−

)3

(aq)

Fe NO

(

₃

)3

(s) ⎯ →⎯ Fe3+(aq)+

(

NO₃2−

)

(aq)

Fe NO

(

₃

)

₃(s) ⎯ →⎯ Fe3+(aq)+ 3NO−₃(aq)

3+ 1- 1- 1- 2+ 1- 1-

Dissolve each solid in an aqueous solutions. You can ALWAYS Figure out the charge of the cation from the anion. The anion is Given in the super green precipitation table.

1 Fe(NO₃)₂(s)---> 2 CuCl₃(s)--->

3 Cu(CrO₄)₂(s)---> 4 Na₂CrO₄(s)---> 5 Cu(CO₃)₂(s)---> 6 Pb(NO₃)₂(s)---> 7 Co₂(SO₄)₃(s)---> 8 Ga₂O₃(s)--->

2K+(aq) + CrO2₄−(aq) + Ba2+(aq) + 2NO₃−(aq) ⎯ →⎯

K₂CrO₄ (s) and Ba(NO₃)₂ (s) placed in water:

In each question, two solids are

1)  Dissolved in two separate beakers 2)  The two solutions are mixed

Write out the first equation that shows how the ions are produced

Then predict the precipitate

Rules for balancing precipitation reactions: 1)  Figure out the precipitate--

2)  Just write down all the other ions after the precipitate 3)  Start with the anion-- is it balanced? If not, chase it

around. Check the ORIGINAL cation…

4)  End with the cation-- is it balanced? If not chase it around. Check the ORIGINAL anion

Precipitation Lab

Work in pairs (three max)

Only hand in ONE final lab per pair--put BOTH your names. If There is only one name, only one mark.

You will find a number of small plastic vials labeled with what Is in it, e.g., NaOH

Your task is to find 4 combinations that will produce precipitates

And 1 that will not

AgNO₃(s)

KCl(s) Both of these solids are dissolved in two beakers

Ions

KNO₃(s)

BaCl₂(s) Both of these solids are dissolved in two beakers

Ions

KOH(s)

Fe NO

(

₃

)

₃(s) Both of these solids are dissolved in two beakers

Ions

AgNO₃(s)

BaCl₂(s) Both of these solids are dissolved in two beakers

Ions

Na₂CO₃(s)

Ca NO

(

₃

)2

(s) Both of these solids are dissolved in two beakers

Ions

NaCl(s)

KNO₃(s) Both of these solids are dissolved in two beakers

Ions

AgNO₃(s)

K₂CrO₄(s) Both of these solids are dissolved in two beakers

Ions

K₂CrO₄(s)

AgNO₃(s) Both of these solids are dissolved in two beakers

Ions

Ba NO

(

₃

)

₂ (s) H₂SO₄(aq)

This is solid

This is an acid and is aqueous Ions

Zach’s Quiz:

Ba NO

(

₃

)

₂ (s)⎯ →⎯

Na₃PO₄(s)⎯ →⎯ Two aqueous solutions

Complete Ionic Equation Net Ionic Equation

NaOH(s)⎯ →⎯

MgCl₂(s)⎯ →⎯ Two aqueous solutions

Precipitation Lab

Work in pairs (three max)

Only hand in ONE final lab per pair--put BOTH your names. If There is only one name, only one mark.

You will find a number of small plastic vials labeled with what Is in it, e.g., NaOH

Your task is to find 6 combinations that will produce precipitates

And 2 that will not

Precipitation Lab

CuCl₂ AgNO₃

1)  AgNO₃(s) Ag+_{(aq) +NO}

3-(aq)

2)  CuCl₂(s) Cu2+_{(aq) + 2Cl}-_(aq)

3)  Ag+_{(aq) + Cl}-_{(aq) AgCl(s)}

QUIZ: Part 2. 10 pts

K₂SO₄(s) NaNO₃(s)

Ba(NO₃)₂(s) K₃PO₄(s)

KOH(s)

Fe NO

(

₃

)

₃(s)

[3]

[4]

Procedure:

1)  Find two vials. Use your super green precipitation table to predict whether or not a precipitate will form or not. 2)  If a precipitate is predicted, then put about 1/2 of an inch

of solution in your test tube. Add the other. Record your observations.

3)  If the prediction was correct, then do this:

Ba NO

(

₃

)

₂ (s)⎯ →⎯

Na₃PO₄(s)⎯ →⎯ Two aqueous solutions

QUIZ!

Part 1: Multiple choice. Choose the correct

precipitate in each case

1)  Ag+ and CrO₄

2-a)  AgCrO₄

b)  Ag₂CrO₄

c)  2AgCrO₄

d)  Ag(CrO₄)₂

2) Fe3+ _{and NO} 3

a) 3FeNO₃ b) Fe(NO₃)₃ c) Fe3(NO₃) d) FeNO₃

3) Ca2+ _{and CO} 3

a) 2CaCO₃ b) Ca(CO₃)₃ c) Ca2(CO₃) d) CaCO₃

4) Ba2+ _{and PO} 4

3-a)  3BaPO₄

b)  Ba₂PO₄

c)  2Ba3PO₄

d)  Ba₃(PO₄)₂

5) Fe3+ _{and CO} 3

The big review

1. You have 0.056 ml of NH₃. The density is 0.87 g/ml. How many molecules of NH₃?

2. Balance the following chemical equation. Use any method you want.

3. Balance the following chemical equation.

4. You have 0.004 grams of Zn. How many grams of H₂ will be produced?

5. You combine a vial of sodium phosphate with barium chloride. a)  Write the chemical formulas of sodium phosphate and barium

chloride.

b)  Predict the precipitate (if any)

c)  Write the net ionic equation.

C

₉

H

₂₀

+

O

₂

⎯ →

⎯

CO

₂

+

H

₂

O

The big test

1. You have 34 ml of H2O. The density is 0.97 g/ml. How many molecules of H2O?

2. Balance the following chemical equation. Use any method you want.

3. Balance the following chemical equation.

4. You have 26.9 grams of Al. How many grams of Al₂S₃ will be produced?

5. You combine a vial of sodium carbonate with magnesium nitrate. a)  Write the chemical formulas of sodium carbonate and magnesium

nitrate.

b)  Predict the precipitate (if any)

c)  Write the net ionic equation.

C

₁₀

H

₂₂

₊

O

₂

_{⎯ →}

_⎯

CO

₂

₊

H

₂

O