ionic compounds containing multivalent ions

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Ionic Compounds Containing Multivalent IonsLearning Goal:Students will name and determine the formula of multivalent compounds

+Ionic Compounds Containing Transition Metals (Multivalent Compounds)

The transition metals are located in groups 3-12 of the periodic table.

The charge on transition metal ions are not easily determined by their location on the periodic table – for reasons you will learn about in Grade 12 Chemistry.

Also, many transition metals have more than one charge (known as an oxidation state).

+Where are the transition metals?

+Eight Important Transition MetalsTransition Metal Possible Ionic ChargesCobalt (Co) 2+ or 3+Chromium (Cr) 3+ or 3+Copper (Cu) 2+ or 1+Iron (Fe) 3+ or 2+Manganese (Mn) 2+ or 4+Mercury (Hg) 2+ or 1+Tin (Sn) 4+ or 2+Lead (Pb) 2+ or 4+Zinc (Zn) 2+ ONLY

Highlight these on the periodic table I gave you in class. The possible charges are listed in the

upper left hand corner for any multivalent metals.

+Naming Multivalent Ions

When naming any ion that has more than one ionic charge, you MUST include a Roman numeral in brackets following the name of the ion.

The Roman numeral is equal to the charge on the ion.

Examples: Cu2+ = copper (II) ion Sn4+ = tin (IV) ion

+Naming Multivalent Ionic Compounds When you name an ionic compound that contains a transition metal

that is multivalent YOU MUST INCLUDE THE ROMAN NUMERAL. CuF2 is NOT named copper fluoride!

Why NOT? Naming the compound copper fluoride does not tell us whether or not the

compound contains a copper (I) or copper (II) ion.

Solution: Determine the charge on the anion first! Then determine the charge the cation must be so that the overall charge of the compound is ZERO.

We know that a fluoride ion always has a charge of 1-. There are 2 fluoride ions in CuF2 this would result in a net charge of 2- This means that the copper had to be 2+.

Therefore the name of the compound is: copper (II) fluoride

+Learning Check: Whiteboards

Name the following compounds:

1) SnI2

2) PbF4

3) CuS

4) CaBr2

5) Mn(NO3)2

6) CoPO4

+Determining the Formula of Multivalent Compounds Write the symbol for each element in the

compound. The roman numeral will tell you the charge on

the metal cation. Determine the charge on the non-metal or

polyatomic anion. Determine how many of each you will need so

that the overall charge is zero.

+Determining the Formula for Multivalent Compounds Example:

iron (II) bromide Fe2+Br1-

Br1-

The chemical formula is FeBr2

cobalt (III) nitrate Co3+ NO31-

NO31-

NO31-

The chemical formula is Co(NO3)3

Watch out of“ide” vs. “ate” and “ite” endings!!!!

“-ide” = simple binary ionic

Any other ending = polyatomic

+Learning Check - Whiteboards

Determine the chemical formula for each of the following:

1) mercury (I) oxide

2) tin (II) nitride

3) manganese (IV) phosphate

4) chromium (III) sulfite

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+Activity - Cubing

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Covalent CompoundsLearning Goal:Students will…

Define covalent compounds Draw lewis dot diagram and structural diagrams for covalent compounds

Name and determine the formula of covalent compounds

+Agenda

Warm-up: Multivalent CompoundsClassifying CompoundsNote: Molecular CompoundsWorksheet: Naming and Determining

Formula of Molecular CompoundsWhiteboard Fun!

+Open Sort: Classifying Compounds Cut out the table of compounds provided

Think: How will you classify the compounds?

Pair: Find a partner.

Share: Describe to your partner how you classified the compounds.

Is there any compounds that look new to you?

+What is a Covalent Compound? A compound formed when non-metal atoms

SHARE electrons. A covalent bond forms as a result of this

sharing of electrons. WHY SHARE ELECTRONS?

By sharing valence electrons, atoms fill their outermost energy level.

Since most atoms require eight valence electrons this is known as the OCTET rule.

+Valence

Example: An oxygen atom has 6 valence electrons. It would need to share two electrons with

other atoms to fill its outer valence. We say that the VALENCE of oxygen is two,

since oxygen forms two bonds.

+Forming Covalent Compounds

If you had 2 oxygen atoms, they would each need to share 2 electrons to fill their valence shell.

Since two pairs of electrons are shared between them a double bond is formed.

LoneElectronPair (unshared)

Shared PairElectrons

Lewis Dot Diagram for O2

+Forming Covalent Compounds

By sharing two pairs of electrons, each oxygen atom has filled their outer shell.

We can also write the Lewis Dot Diagram to show which electrons are being shared. A straight line equals one pair of shared electrons.

+Remember…

All of the following elements are found as diatomic molecules at room temperature:

HOFBrINCl

+Drawing Lewis Dot Diagrams of Covalent Compounds Example: HCl1. Draw the lewis dot diagram for each

element.2. Re-arrange the electrons so that each non-

metal atom achieves stability by filling its outer valence orbit.

+Try These…

Draw the Lewis Dot Diagram for the following covalent compounds.

HINT…the atom with the highest valence (can form the most bonds) goes in the middle)

a) CO2

b) H2O

c) CF4

+Naming Covalent Compounds

When naming covalent compounds you can distinguish them from ionic compounds because…

IONIC COMPOUNDS USUALLY BEGIN WITH A METAL! COVALENT COMPOUNDS CONTAIN TWO NON-METAL

ELEMENTS ONLY! Use the following system for naming covalent

compounds:(prefix if more than one) non-metal + (prefix always) non-

metal “ide”

+Examples:

CO NH3

N2O5

IF5

PREFIXES

mono-1

di- 2tri- 3tetra-

4penta-

5hexa- 6hepta-

7octa- 8hexa-

9deca- 10

carbon monoxide

nitrogen trihydride

dinitrogen pentoxideIodine pentafluoride

+Determining the Formula of Covalent Compounds Use the prefixes to determine the subscripts

in the chemical formula… chlorine dioxide tetraphosphorus trisulfide sulfur hexafluoride Diphosphorus pentaoxide

ClO2

P4S3

SF6

P2O5

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+Homework

Molecular Compounds Worksheet & Putting It All Together