(Exp. 2A)

Heating Curve of Water

-25

0

25

50

75

100

125

Time

Tem

pera

ture

boiling pointboiling point

melting pointmelting point

liquidliquid

gasgas

solidsolid

Heating Curve of Mixture of Water and Alcohol

-50

0

50

100

150

Time

Tem

pera

ture

Conclusion• Pure substances change phases at

constant temperature.

• Melting points and boiling points can be used to determine the identity of a substance and whether or not a substance is pure.

NEED TO KNOW:• Symbols & names 1-36• State of elements at room temps.• Periods vs. groups

(rows) (columns)• Metals vs. non-Metals

(lose e-) (gain e-)• Atomic Number = # of protons• Atomic Mass (Mass #) = # of protons + # of neutrons• Atomic Radius (page 319 in textbook)• Characteristic charges of groups (alkali metals = 1+)• Groups: Alkali Metals, Alkaline Earth Metals,

Transition Metals, Halogens, Noble Gases

Chemistry 11 Unit 3

• In an ionic compound, positive charges must balance the negative charges.

e.g.: What is the formula for magnesium phosphide?

Magnesium is Mg2+ Phosphorous is P3-

Lowest common multiple of 2 and 3 is 6

3 Mg2+ ions and 2 P3– ions

Mg3P2

e.g.: What is the formula for calcium oxide?

Calcium is Ca2+ Oxygen is O2-

1 Ca2+ ion and 1 O2– ion

CaO

(remember, the subscript 1 is never written)

Mg2+ P3-

Mg2+ P3-

Mg2+

6+ 6-

Mg3P2

1. Write both symbols (+ion first) with ion charge

2. Criss-cross the charges and write them as subscripts

3. Reduce if possible

Mg O2+ 2-

(remember, the subscript 1 is never written)

Mg O22

MgO

Only use if you understand that the + and - charges must balance!

Magnesium oxide

Sometimes, metal ions have more than one combining capacity

Fe O2+ 2-

FeO

e.g. Cu2+ Cu1+

Fe3+ Fe2+

The name of the compound will include a roman numeral that tells you which combining capacity to use

Iron II oxidee.g. Iron III oxide

Fe O3+ 2-

Fe2O3

1+ I 2+ II 3+ III 4+ IV

5+ V 6+ VI 7+ VII

1. Write the name of the metal first.

2. Write the name of the non-metal second, and change the ending to “-ide”

3. ONLY IF THE METAL HAS 2 OR MORE COMBINING CAPACITIES, Include a roman numeral to indicate which one it is.

e.g. NaCl

MgF2

CuCl2

Sodium chloride

Magnesium fluoride

copper has 2 ions: Cu 1+

Cu 2+

which one is it?

To find out which copper ion it is, look at the charge on the anion and balance the charges in reverse.

CuCl therefore must be copper I chloride

Cu Cl2+ 1-

CuCl2

Therefore it is copper II chloride

from periodic table

Cl 1-

2-

Name and write the formulas for:

a) chlorine & aluminum

b) bromine & sodium

c) magnesium & sulphur

d) calcium & nitrogen

e) fluorine & beryllium

Aluminum chloride; AlCl3

Sodium bromide; NaBr

Magnesium sulphide; MgS

Calcium nitride; Ca3N2

Beryllium fluoride; BeF2

Name and determine the charge on each of the transition metals in the following compounds:

a) CuO

b) FeAs

c) CrBr3

d) Cu2O

e) FeCl3

Copper II oxide; Cu2+

Iron III arsenide; Fe3+

Chromium III bromide; Cr3+

Copper I oxide; Cu+

Iron III chloride; Fe3+

f) CrCl2 Chromium II chloride; Cr2+

• Some groups of atoms act as individual ions

e.g. SO4-2 Sulphate ion -2

OH-1 Hydroxide ion -1

PO4-3 Phosphate ion -3

• When writing formulas and naming, pretend the polyatomic ion is just one atom and follow the rules as usual.

e.g. K+1 -3

K3PO4Potassium phosphate

Don’t change the endings of polyatomic ions

Ion Charge

PO4

Aluminum sulphate

Copper (II) sulphate

Al SO4+3 -2 Al2(SO4)3

Cu+2CuSO4

Put brackets around the SO4 to indicate 3 sulphate ions, not 43 oxygen atoms

SO4-2

Don’t forget the roman numeral since copper has more than one combining capacity

See the back of your periodic table for the names and formulas of important polyatomic ions.

• Hydrates are ionic compounds with water molecules attached

e.g.

- each copper II sulphate is attached to 5 water molecules

CuSO4 • 5H2O

Copper II sulphate pentahydrate

e.g.

FeSO4 • 6H2O

Iron II sulphate hexahydrate

HCl

HF

HNO3

Hydrochloric acid

Hydrofluoric acid

Nitric acid

HNO2

H2SO4

Nitrous acid

Sulphuric acid

If the anion name ends in ide:the acid name starts with hydro and ends with ic acid. eg: HCl:

Cl- is chloride. So HCl is hydrochloric acid.

If the anion name ends in ate:the acid name ends with ic acid; no hydro prefix. eg: HNO3:

NO3- is nitrate. So HNO3 is nitric acid.

If the anion name ends in ite:the acid name ends with ous acid; no hydro prefix. eg: HNO2:

NO2- is nitrite. So HNO2 is nitrous acid.

• Compounds composed of two non-metal elements• More metallic name comes first, • then use a prefix to show the number of atoms of the less

metallic element, followed by the –ide ending

Name the following compounds:a) CO2 Carbon dioxideb) CO Carbon monoxidec) PCl3 Phosphorous trichlorided) CCl4 Carbon tetrachloridee) PF5 Phosphorous pentafluoridef) H2O Dihydrogen monoxidea) S2O4 Disulphur tetraoxide

“Naming & Formula I” WorksheetQuiz on Periodic Table next class

Homework: