41

Why does an element want to bond? - Polk County School ... formulas and... · 1). Write the symbol and charge for the cation. 2). Write the symbol and charge for the anion. 3). _____

  • Upload
    lycong

  • View
    216

  • Download
    2

Embed Size (px)

Citation preview

Why does an element want to bond?

State 3 differences between ionic vs.

covalent compounds

What is a chemical formula?

It indicates the relative _________________

of each kind in an ionic compound.

Ex Al2O3 has ________________________________

It indicates the number of atoms of each

element contained in a single molecule of a

molecular compound.

Ex. C8H18 has 8 atoms of carbon and 18 atoms of

H in a molecule of octane.

There are different rules for naming and writing formulas for ionic and covalent compounds.

The compound is ionic if it is composed of a _________ and an________, or a_______ and a ________. The elements will be located on _________ sides of the periodic table. They have a high ___________________difference.

The compound is ___________ (or molecular) if both elements are nonmetals.

Binary because composed of only___

elements.

Ionic because composed of a metal

and a nonmetal.

Example ______________________

1). Write the symbol and charge for the cation.

2). Write the symbol and charge for the anion.

3). ________ the oxidation numbers and

______ the charges. The oxidation number

will become the subscript for the other

element.

4). ______ the subscripts if possible. If they

are the same, they __________ completely.

5). If the subscript is ___, do not write

anything.

Write the formula for calcium iodide.

Write symbols and charges.

Criss-cross oxidation numbers, drop charges.

Cancel and take away ones.

Question: Write the formula for Magnesium

Oxide.

1) Write the symbol and charge.

2) Criss cross oxidation number and drop

charges.

3). Cancel and don’t write 1’s.

Complete page 4 and the bottom of page 5 of

formula writing packet.

If a compound consists of a metal and a

nonmetal, we use the name of the first

element (always the cation) followed by the

second element (always the anion). For the

anion only, drop the last syllable and add

________. Subscripts are not included in

the name.

Examples: CaO:

LiCl:

K2S:

P. 223 sample problem A

P. 223 practice #1 a-e, and #2 a-f

Complete packet page 1 and 8.

Some elements, such

as______________________, form 2 or more

cations with different charges. To distinguish

the ions formed by such elements, scientists

use the Stock system of nomenclature. This

system uses a ______numeral to indicate the

ion’s charge. The numeral is enclosed in

parentheses and placed immediately after

the metal name.

Fe+2 is _________ and Fe+3 is _____________

Names of metals that commonly form only

one cation, do not include a Roman numeral.

CuCl2

Determine the charges of each element, by

writing ions side by side.

Backwards criss-cross to determine charge of

cation.

Name by writing name of cation , roman

numeral, name of anion with ide instead of

last syllable.

Example: Write the formula of lead(IV)

oxide.

Write symbols with charge.

Criss cross and drop signs.

Reduce and remove 1’s.

Page 225 #1(a-f) and #2 (a-d)

Complete packet page 3 and 5(top)

A ___________ bonded group of atoms that has

a positive or negative charge and act as a

unit is a polyatomic ion.

The prefix poly means “many”.

Most simple polyatomic ions are ________.

____________________ is the only

polyatomic cation.

Sometimes there are ______________in the

formula, so you can tell its polyatomic.

If it contains a polyatomic ion, it is ____________, so it follows the rules for naming ionic compounds.

If anion is polyatomic, ________________________. Keep it the same as is listed on the chart. Name cation then name anion.

If the cation is polyatomic and the anion is binary, name is just like before. The______ ending means the anion is not polyatomic.

Al2(SO4)3

Fe(OH)2

1. Write the symbols for the monatomic and polyatomic ions in the compound.

2. Look up the oxidation numbers of the ions involved.

If a single atom, use the periodic table.

If roman numeral (variable oxidation number) or polyatomic, use the chart.

3. Criss cross the oxidation numbers, and drop the charges.

4. Put polyatomic ions in _________ if they have a subscript.

5. Reduce (simplify) and erase ones.

6. DO NOT ADD< SUBTRACT, MULTIPLY, OR DIVIDE. Just criss cross and reduce if necessary!

Write the formula for Lead (II) hydroxide.

1. Write the symbol and oxidation number.

2. Criss cross charges and drop signs.

3. Use parentheses if needed.

4. Reduce and drop 1’s.

Write the formula for ammonium sulfate.

1. Write the symbol and oxidation number.

2. Criss cross charges and drop signs. Use

parentheses if needed.

3. Reduce and drop 1’s

Pringles—ammonium phosphate

Bisquick—sodium hydrogen carbonate

(sodium bicarbonate)

Mac ‘n cheese-calcium phosphate

Bacon bits—sodium nitrite

Magnesium hydroxide

Ferric sulfate

Calcium nitride

Aluminum phosphide

Check answers using the key provided online.

www.gavirtuallearning.org

Resources

Shared—”Click here”

Science—left side

Chemistry—left side

Chemical formulas & equations—”View”

Tab 4

Gray box on right side of page---”Binary &

Ternary Compound key”

Naming: 2, 3, 4, 7,10 only

Add: WRITE FORMULA

1. plumbic oxide

2. stannous carbonate

3. aluminum nitride

4. strontium phosphate

5. gallium hydroxide

Molecular/covalent compounds are made of 2 nonmetals.

Generally, the most metallic element is written first. These elements are farther to the left in the periodic table. If both elements are in the same group, the more metallic element is closer to the bottom of the group.

The name of the second element is changed to

-ide.

Because molecular formulas can combine in many combinations, _________ are used to indicate the subscript. ____________________________________________________

Don’t use______ on _______ element.

1- mono

2- di

3- tri

4- tetra

5- penta

6- hexa

7- hepta

8- octa

9- nona

10- deca

Write the symbols for the elements in the

order that they appear in the name.

The _______indicate the number of atoms of

each element in the molecule.

The prefixes appear as ___________in the

formulas.

If there is no prefix, there is only one atom.

(_______ element only)

Remember, do not_________.

Example tetraphosphorus dichloride

Write the formula:

1. Dibromine heptasulfide

2. Selenium tetrafluoride

3. Carbon monoxide

4. Nitrogen trichloride

Name:

1. NO

2. P2O5

3. P Cl3

4. C I4

Write formulas for:

1. Zinc nitride

2. Boron trifluoride

3. Calcium hydroxide

4. Plumbic selenide 5. aluminum dichromate

Name these:

***1ST PUT I (ionic) OR C (covalent) BESIDE THE

QUESTION

FRONT LEFT COLUMN:

1—20, 25, 26

FRONT RIGHT COLUMN:

1—18, 23, 25, 26

What do I

know about

acids?

What do I

want to

know about

acids?

What have I

learned

today about

acids?

What element do ALL acids start with?

If the acid is binary use prefix “_________”

AND the suffix “_____”.

If the acid is ternary, do not use a prefix but

change the polyatomic anion

ATE=_________

ITE= __________

HF

HNO3

H2SO3

HBr

HC2H3O2

HClO

H3PO4

All will end in the word “acid”.

You must “__________________”

like you did for ionic.

Example: chromic acid

Example: hydroiodic acid

Benzoic acid

Hydrochloric acid

Cyanic acid

Chlorous acid

Carbonic acid

Hydrobromic acid

Arsenous acid

WRITE FORMULA: NAME:

1.hydrofluoric acid 1. H2 SO3

2.arsenous acid 2. H Br

3. acetic acid 3.HCl

4. hydroiodic acid 4. H2CO3

5. phosphoric acid 5. H IO4

Silicon tetrabromide

Diphosphorus pentasulfide