Calcium + Silicon

Sodium + Bromine

Boron + Fluorine

Potassium + Sulfur

Ca+2

+

Na+1 +

B+3 +K+1 +

Si-4 Ca2Si

NaBrBr-1

F-1 BF3

S-2 K2S

Bellwork: Wednesday 4/11/2012 Write formulas for how the following elements would form Ionic compounds

Example #1-Names to Formulas

Aluminum chloride

Al Cl3

2. Determine number of ions

1. Write symbols of elements

Final Formula

x(+3) + y(-1) = 0

1

If there is only one atom the “1” is not shown

+3(Al )x(Cl-1)y

1(+3) + 3(-1) = 0

This formula says that the +3 charge of one Alatom will cancel the-3 charge from 3 Cl atoms

Example #2-Names to Formulas

Cobalt (II) bromate

Co BrO3

2. Determine number of ions

1. Write symbols of elements

Final Formula

(Co+2)x(BrO3-1)y

= 0

2X = 1yX(+2) + y(-1) = 0

X 1Y 2=

1Choose the

lowest set of integers

thatsatisfies the

equation

If there is only one atom the “1” is not shown

( )2

Example #3-Names to Formulas

Nickel (III) acetate

Ni C2H3O2

2. Determine number of ions

1. Write symbols of elements

Final Formula

(Ni+3)x(C2H3O2-1)y

= 0

3X = 1y

X(+3) + y(-1) = 0

X 1Y 3=

1Choose the

lowest set of integers

thatsatisfies the

equation

( )3

If there is only one atom the “1” is not shown

Example #4-Names to Formulas

Lithium phosphate

Li PO4

2. Determine number of ions

1. Write symbols of elements

Final Formula

(Li )x(PO4-3)y

= 0

1X = 3y

X(+1) + y(-3) = 0

X 3Y 1=

3

+1

( )1

If there is only one atom the “1” is not shown

Names to Formulas: Criss-Cross Method

Barium nitrate1. Write the formulas for the cation and anion, including CHARGES! Ba2+ NO3

-

2. Check to see if charges are balanced.

3. Balance charges, if necessary, using subscripts. Use parentheses if you need more than one of a polyatomic ion. Use the criss-cross method to balance the subscripts.

Not balanced!

( ) 2Now balanced.

= Ba(NO3)2

Iron (III) chloride

Fe3+ Cl-

Not balanced!

3Now balanced.

= FeCl3

Names to Formulas: Criss-Cross Method

1. Write the formulas for the cation and anion, including CHARGES!

2. Check to see if charges are balanced.

3. Balance charges, if necessary, using subscripts. Use parentheses if you need more than one of a polyatomic ion. Use the criss-cross method to balance the subscripts.

Ammonium sulfate

NH4+ SO4

2-

Not balanced!

( )2

Now balanced.

= (NH4)2SO4

Names to Formulas: Criss-Cross Method

1. Write the formulas for the cation and anion, including CHARGES!

2. Check to see if charges are balanced.

3. Balance charges, if necessary, using subscripts. Use parentheses if you need more than one of a polyatomic ion. Use the criss-cross method to balance the subscripts.

Aluminum sulfide

Al3+ S2-

Not balanced!

2 3Now balanced.

= Al2S3

Names to Formulas: Criss-Cross Method

1. Write the formulas for the cation and anion, including CHARGES!

2. Check to see if charges are balanced.

3. Balance charges, if necessary, using subscripts. Use parentheses if you need more than one of a polyatomic ion. Use the criss-cross method to balance the subscripts.

DNA- The Master Molecule of Life- page 12

Deoxyribonucleic Acid (DNA): A long, large molecule shaped like a twisted ladder (double helix). The plans for who you are and what you look like are chemically stored in the DNA (like a blueprint). In 1953, Francis Crick and James

Watson discovered that DNA is shaped like a ladder coiled into a 'double helix' shape.

Macromolecule: A very large molecule made from thousands of atoms (ex. DNA)

VIDEO- DNA: Master Molecule of LifeAs you watch the following videos, fill out

the video guide provided- page 12

Video- Importance of DNA 1.341. Molecule2. Cells3. Molecules/

DNA4. Genetic code5. True

Video- DNA Subunits 3.456. Macromolecule7. 28. False9. 410. Backbone11. A and T, G and

C

Components of DNANucleotide Subunit: what DNA is made up of; each nucleotide has: ‘Sides’ of the ladder-

(linked chains of alternating sugar and phosphate molecules) phosphate sugar

‘Rungs’ of the ladder- 2 nitrogenous (nitrogen-containing) bases attached to the sugar molecules (4 different types of bases)Adenine (A)Thymine (T)Cytosine (C)Guanine (G)

○ They link together in pairs (A with T, C with G) to form a rung

○ The order of the bases and rungs creates a kind of code for the DNA information.

Sides of the ladder: “Sugar-Phosphate Backbone” Phosphate PO4

3−

Polyatomic Ion!Octet Rule- atoms tend to

gain, lose, or share electrons until they have eight electrons in their valence shell.

Given what you know about the chemical formula for the phosphate functional group, you can say that the rule is disobeyed in this case.

Sugar (deoxyribose)5 carbon ringEach corner of the

pentagon represents a Carbon—they just don’t write it!

Page 13- What five elements make up the DNA macromolecule?

1. Phosphorus

2. Carbon

3. Hydrogen

4. Oxygen

5. Nitrogen

The DNA double helix is stabilized by hydrogen bonds between the bases attached to the two strands.

AT base pair With two hydrogen bonds Hydrogen bonds are shown as dashed lines

GC base pair

With three hydrogen bonds

DNA Sequencing- page 13 PRACTICE: What would be the pair for:

Finish the DNA sequencing individually, then check answers together as a class

ACCTGG

GAC TACCTG ATG

ATCTAG CGA

GCTTGA

ACT CTCGTA ATC CGTACA

GAG CAT TAGGCA TGT

Increasing knowledge about DNA creates more complicated

possibilities for the future… Cloning- the

process of making a genetically identical organism through nonsexual means

Natural cloning is identical twinsgenetically

different from parents

What do you think about the possibilities for human cloning?

If you could make a clone of yourself, would you do it?Why or why not?Record your

answers in the space provided

Cloning- KWL— Fill -in the “Know” and “Wonder”

column NOWKnow Wonder Learned

1. 2.

things you already know about cloning

1.2.

things you wonder about

cloning

1.2.3.4.

things you learned about cloning during that will follow

Video: The Clone AgeAs you watch the video… …write four new things you

learned on your KWL chart- page 13

…pay attention to the scientific process involved in creating a clone

…note where hereditary information is stored in a cell and how this information may be altered

1st Cloned Mammal

1997- Scotland Sheep named Dolly 276 attempts before

successWhat do you think happened

to the unsuccessful attempts??

Dolly

Dolly’s clone—

NOT her

baby!

Remaining Time: Discuss questions as a class.

Respond to the following questions in 3-4 complete sentences on page 13 for homework.

1. Discuss the ethics of cloning only the best and brightest of the human race.

2. If you were in charge of undertaking a cloning project, which qualities would you look for when selecting your cloning subjects? Explain why.

EXTRA TIME? Practice Ionic Naming

Formulas to Names & Names to Formulas1. Na2SO4

2. Fe(NO3)2

3. PbI44. (NH4)3PO4

5. Na2CO3

6. Be(OH)2

7. Magnesium Hydroxide

8. Magnesium nitride

9. Silver Acetate10.Aluminum

Chloride

1. Sodium Sulfate2. Iron (II) Nitrate3. Lead (IV) iodide4. Ammonium

Phosphate5. Sodium carbonate6. Beryllium

Hydroxide7. Mg(OH)2

8. Mg3N2

9. AgC2H3O2

10.AlCl3

EXTRA TIME? Practice Ionic Naming

Names to Formulas1. Calcium Carbonate2. Potassium Chloride3. Iron (II) Sulfate4. Lithium bromide5. Magnesium chloride6. Iron (III) chloride7. Zinc Phosphate8. Ammonium Nitrate9. Aluminum hydroxide10. Copper (I) Acetate11. Lead (II) Sulfite12. Sodium Chlorate13. Calcium Oxalate

14.Iron (III) Oxide15.Ammonium Phosphate16.Sodium hydrogen sulfate17.Mercury (I) chloride18.Magnesium nitrate19.Copper (II) sulfate20.Sodium hydrogen

carbonate21.Nickel (III) bromide22.Beryllium nitrate23.Zinc sulfate24.Gold (III) chloride25.Potassium

permanganate