Chemical Reactions

Chapter 11

Do Now- In your own words Write an explanation for what Is happening in this picture.

Objective- 11.1 Describing Chemical Reactions

HW – Pg 329 # 9-12

11.1 Describing Chemical Reactions

• Word Equations

11.1 Describing Chemical Reactions

• Word Equations

Reactants → Products

11.1 Describing Chemical Reactions

• Word Equations

Reactants → Products

iron + oxygen → iron(III) oxide

Symbols Used in Chemical Reactions

+→↔(s)(l)(g)(aq)Heat ∆Pt

Symbols Used in Chemical Reactions

+ Separates two reactant and two products→ “Yields” Separates reactants from products↔ Reaction is reversible (s) solid(l) liquid (g) gas(aq) aqueous solutionheat ∆ heat was supplied to reactionPt Element (Pt) used as catalyst

• Chemical Equations

Reactants → Products iron + oxygen → iron(III) oxide Fe + O2 → Fe2O3

→

• Chemical Equations

Reactants → Products iron + oxygen → iron(III) oxide Fe + O2 → Fe2O3

4Fe(s) + 3O2(g) → 2Fe2O3 (s)

Magnesium + Oxygen → Magnesium oxide

Magnesium + Oxygen → Magnesium oxide

Mg + O2 → MgO

Magnesium + Oxygen → Magnesium oxide

Mg + O2 → MgO

2Mg + O2 → 2MgO

• Do Now - Write the ionic or molecular formula for Lithium Oxide

Aluminum SulfideSilicon Oxide

• Objective – Balance Chemical Equations

• Homework – finish Pg. 329 # 9 – 12 and handout

Balancing Chemical Equations

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1. Determine correct formulas for all reactants and products. 2. Write a skeleton equation. 3. Determine the number of atoms of each element on the reactant side and the product side.

4. Balance the number of atoms of each element by adding coefficients. (The subscripts can’t be changed now)

5. Check that the number of atoms of each element is the same on both sides. 6. Check to see that all coefficients are in lowest whole number ratio possible.

Iron + oxygen → iron oxide

Fe + O2 → Fe2O3

1. Determine correct formulas for all reactants and products. 2. Write a skeleton equation. 3. Determine the number of atoms of each element on the reactant side and the product side.

4. Balance the number of atoms of each element by adding coefficients. (The subscripts can’t be changed now)

5. Check that the number of atoms of each element is the same on both sides. 6. Check to see that all coefficients are in lowest whole number ratio possible.

Iron + oxygen → iron oxide

Fe + O2 → Fe2O3

Fe Fe O O

1. Determine correct formulas for all reactants and products. 2. Write a skeleton equation. 3. Determine the number of atoms of each element on the reactant side and the product side.

4. Balance the number of atoms of each element by adding coefficients. (The subscripts can’t be changed now)

5. Check that the number of atoms of each element is the same on both sides. 6. Check to see that all coefficients are in lowest whole number ratio possible.

Iron + oxygen → iron oxide

Fe + O2 → Fe2O3

Fe 1 Fe 2O 2 O 3

1. Determine correct formulas for all reactants and products. 2. Write a skeleton equation. 3. Determine the number of atoms of each element on the reactant side and the product side.

4. Balance the number of atoms of each element by adding coefficients. (The subscripts can’t be changed now)

5. Check that the number of atoms of each element is the same on both sides. 6. Check to see that all coefficients are in lowest whole number ratio possible.

Iron + oxygen → iron oxide

Fe + O2 → Fe2O3

Fe 1 Fe 2O 2 O 3

Fe + O2 → Fe2O3

Fe 1 Fe 2O 2 O 3

1. Determine correct formulas for all reactants and products. 2. Write a skeleton equation. 3. Determine the number of atoms of each element on the reactant side and the product side.

4. Balance the number of atoms of each element by adding coefficients. (The subscripts can’t be changed now)

5. Check that the number of atoms of each element is the same on both sides. 6. Check to see that all coefficients are in lowest whole number ratio possible.

Iron + oxygen → iron oxide

Fe + O2 → Fe2O3

Fe 1 Fe 2O 2 O 3

Fe + O2 → Fe2O3

Fe 1 Fe 2O 2 O 3

Fe + O2 → Fe2O3

Fe Fe O O

1. Determine correct formulas for all reactants and products. 2. Write a skeleton equation. 3. Determine the number of atoms of each element on the reactant side and the product side.

4. Balance the number of atoms of each element by adding coefficients. (The subscripts can’t be changed now)

5. Check that the number of atoms of each element is the same on both sides. 6. Check to see that all coefficients are in lowest whole number ratio possible.

Iron + oxygen → iron oxide

Fe + O2 → Fe2O3

Fe 1 Fe 2O 2 O 3

Fe + O2 → Fe2O3

Fe 1 Fe 2O 2 O 3

4Fe + 3O2 → 2Fe2O3

Fe 4 Fe 4O 6 O 6

1. Determine correct formulas for all reactants and products. 2. Write a skeleton equation. 3. Determine the number of atoms of each element on the reactant side and the product side.

4. Balance the number of atoms of each element by adding coefficients. (The subscripts can’t be changed now)

5. Check that the number of atoms of each element is the same on both sides. 6. Check to see that all coefficients are in lowest whole number ratio possible.

Iron + oxygen → iron oxide

Fe + O2 → Fe2O3

Fe 1 Fe 2O 2 O 3

Fe + O2 → Fe2O3

Fe 1 Fe 2O 2 O 3

4Fe + 3O2 → 2Fe2O3

Fe 4 Fe 4O 6 O 6

4Fe + 3O2 → 2Fe2O3