Catalyst – October 2(6)-1, 2010

Monday Mystery Element

1. Used in space shuttle parts

2. One of its compounds looks like a diamond

3. Its name probably originated from the Arabic word “zargun”

Sit where you like, but make sure you can stay focused and see the

board!

Catalyst – October 2(6)-1, 2010

Monday Mystery Element

1. Used in space shuttle parts

2. One of its compounds looks like a diamond

3. Its name probably originated from the Arabic word “zargun”

ZIRCONIUM!

Today’s Agenda

Catalyst Chemistry Prom Begins! Intro to Unit 4 – Chemical

Reactions! Practice Time! Exit Question

Today’s Objectives

SWBAT interpret chemical equations.

SWBAT write skeleton (formula) equations from word equations.

What is a CHEMICAL REACTION???

What to Expect at Chemistry Prom

Learn how to interpret and write chemical reactions

Learn about 5 types of chemical reactions

Show off your chemical dance movesCrown a Chemistry Prom King and Queen from each class

Remember Chemistry Prom with a Project

Chemistry Prom King and Queen Eligibility Requirements

Complete all homework on time

Stay focused in class Complete all classwork No sleeping Miss no more than one day of school this week

The Element Song!

http://www.privatehand.com/flash/elements.html

Do you know what a chemical reaction is????

Key Point #1: A chemical reaction is a process involving one or more substances changing into NEW SUBSTANCES.

DANCE FLOOR TIME!Chemical Reaction: YES or NO?1. Milk going sour2. Cutting a piece of paper3. Eggs rotting4. Baking soda and vinegar mixing to

produce carbon dioxide5. Crushing an aluminum can before

recycling it6. Recycling an aluminum can7. Mg + O2 MgO

Chemical Equations!

Key Point #2: We use CHEMICAL EQUATIONS to show what happens in chemical reactions.C3H8 + 5 O2 3 CO2 + 4

H20

Chemical Equations

Chemical equations are similar to algebraic equations in that the total number of atoms of each element must be equal on each side

A mathematical equation: x + 2x = 3x

A chemical equation:C3H8 + 5 O2 3 CO2 + 4 H20

Parts of a Chemical EquationKey Point #3: A chemical equation identifies the starting chemicals as REACTANTS and the finishing chemicals as PRODUCTS.

Reactants ProductsExample (combustion of propane)

C3H8 + 5 O2 3 CO2 + 4 H20

3 Types of Chemical Equations

There are 3 ways to write chemical

equations:1. Word Equations2. Skeleton Equations

3. Balanced Equations

Phase Notations

There are 4 phase notations used in

equations:1. Solid (s)2. Liquid (l)3. Gas (g)4. In water/Aqueous

(aq)

Parts of Chemical Equations

Reactants ProductsC3H8 + 5 O2 3 CO2 + 4

H20

When you see

“yields” or “produces

” or “forms,” use an

arrow ()

When you see

“reacts with” or

“and,” use a plus sign

(+)

Word Equations

Key Point #4: Word equations use WORDS to show chemical reactions.

Solid iron and chlorine gas react to form solid iron(III)

chlorideIt’s like a short “chemical sentence” describing a chemical reaction!

Skeleton Equations

Key Point #5: Skeleton equations use CHEMICAL FORMULAS rather than words to identify products and reactants.

Word Skeleton Examples

1. Write the skeleton equation from the following word equation:Solid iron and chlorine gas react to form solid iron(III) chloride.

Just replace all names with formulas!

Don’t forget phase notations!

Write the skeleton equation…

Solid iron and chlorine gas react to form solid iron(III) chloride.

Metals: Just write the element symbol Diatomics: Molecules with 2 atoms of the

same element Start at 7, make a 7, don’t forget the “H!”

Skeleton Equation:Fe (s) + Cl2 (g) FeCl3 (s)

Skeleton Equations – Examples

Write skeleton equations for the following word equations:

1.Solid magnesium and chlorine gas react to form solid magnesium chloride.

2.The reaction of hydrogen gas and bromine gas yields hydrogen bromide gas.

3.Aqueous sodium hydroxide reacts with aqueous hydrogen chloride to produce aqueous sodium chloride and liquid dihydrogen monoxide.

Skeleton Equations – Your Turn!

Write the skeleton equations for the following word equations:

1. Hydrogen gas reacts with iodine gas to yield gaseous hydrogen iodide.

2. Gaseous carbon monoxide reacts with oxygen gas to produce carbon dioxide gas.

3.Solid potassium chlorate (chlorate = ClO3

1-) yields solid potassium chloride and oxygen gas.

TURN IN CLASSWORK TO FOLDER

Exit QuestionHW: BOTH SIDES OF WORKSHEET1. What is written on the LEFT side of the

arrow in a chemical equation: PRODUCTS or REACTANTS?

2. Which of the following is a correctly written SKELETON EQUATION for reaction between solid lithium and oxygen gas?

A) Li + O LiOB) Li + O2 Li2O

C) Li (s) + O2 (g) Li2O (s)

D) LiO Li + O