## Chapter 5 & 9: Chemical Reactions, Acids, and Bases

Here's a summarized outline of the PDF, incorporating bullet points, tables, and quizzes for better comprehension and memorization.

**Chapter 5: Chemical Reactions**

**5.1 Introduction to Chemical Reactions**

* **Physical Change:** Alters the physical state of a substance without changing its composition.
* **Chemical Change:** Converts one substance into another by breaking bonds in reactants and forming new bonds in products.

**5.2 Balancing Chemical Equations**

1. Write the equation with correct formulas.
2. Balance the equation with coefficients one element at a time.
3. Check to make sure the smallest set of whole numbers is used.

**5.3 Types of Reactions**

| Type of Reaction | Description | Example |
|---|---|---|
| Combination | Joining of two or more reactants to form a single product | A + B → AB |
| Decomposition | Conversion of a single reactant to two or more products | AB → A + B |
| Single Replacement | One element replaces another element in a compound | A + BC → AC + B |
| Double Replacement | Two compounds exchange "parts" to form two new compounds | AB + CD → AD + CB |

**5.4 Oxidation and Reduction**

* **Oxidation:** Loss of electrons from an atom.
* **Reduction:** Gain of electrons by an atom.
* **Redox Reaction:** Involves the transfer of electrons from one element to another.
* **Oxidizing agent:** Causes another compound to be oxidized (itself gets reduced).
* **Reducing agent:** Causes another compound to be reduced (itself gets oxidized).
* **Examples:**
* Iron rusting (4Fe + 3O2 → 2Fe2O3)
* Zn + 2MnO2 → ZnO + Mn2O3

**5.5 The Mole and Avogadro's Number**

* **Mole:** A quantity containing 6.02 x 10^23 items.
* **Avogadro's Number:** 6.02 x 10^23.

**5.6 Mass to Mole Conversions**

* **Formula weight:** Sum of atomic weights of all atoms in a compound (amu).
* **Molar mass:** Mass of one mole of any substance (g/mol).
* Relates number of moles to grams of a substance.

**5.7 Mole Calculations in Chemical Equations**

* Balanced equations indicate the number of moles of each reactant and product.
* **Mole ratios:** Serve as conversion factors.

**5.8 Mass Calculations in Chemical Equations**

* Convert moles of reactant to grams of product using mole ratios and molar mass.

**5.9 Percent Yield**

* **Theoretical yield:** Expected amount of product based on balanced equation.
* **Actual yield:** Isolated amount of product from a reaction.
* **Percent yield = (actual yield / theoretical yield) x 100%**

**5.10 Limiting Reactants**

* **Limiting reactant:** Completely used up in a reaction.
* Determines the maximum amount of product that can be formed.

**Quiz 5 (Chapter 5)**

**Question 1:** What type of reaction is represented by the equation: A + BC → AC + B ?

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<summary>Answer</summary>
Single Replacement
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**Question 2:** What is the molar mass of H2O (Hydrogen: 1 g/mol, Oxygen: 16 g/mol)?

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<summary>Answer</summary>
18 g/mol
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**Question 3:** What is Avogadro's number?

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<summary>Answer</summary>
6.02 x 10^23
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**Question 4:** In a chemical reaction, the substance that is completely used up is called the:

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<summary>Answer</summary>
Limiting reactant
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**Chapter 9: Acids and Bases**

**9.1 Introduction to Acids and Bases**

* **Arrhenius Definition:**
* Acid: Contains hydrogen and forms H+ in water.
* Base: Contains hydroxide and forms OH- in water.
* **Brønsted-Lowry Definition:**
* Acid: Proton (H+) donor.
* Base: Proton (H+) acceptor.

**9.2 The Reaction of a Brønsted-Lowry Acid with a Brønsted-Lowry Base**

* **Conjugate base:** Formed by loss of a proton from an acid.
* **Conjugate acid:** Formed by gain of a proton by a base.
* **Amphoteric compound:** Can act as both an acid and a base (e.g., water).

**9.3 Acid and Base Strength**

* **Strong acid:** Dissociates completely in water (e.g., HCl, H2SO4).
* **Weak acid:** Dissociates partially in water (e.g., H3PO4, HF).
* **Strong base:** Dissociates completely in water (e.g., NaOH, KOH).
* **Weak base:** Dissociates partially in water (e.g., NH3).

**9.4 Dissociation of Water**

* Water can act as both an acid and a base, reacting with itself.

**9.5 The Ion-Product Constant for Water (Kw)**

* Kw = [H3O+][OH-] = 1.0 x 10^-14 at 25°C.

**9.6 The pH Scale**

* pH = -log[H3O+].
* Acidic solution: pH < 7.
* Basic solution: pH > 7.
* Neutral solution: pH = 7.

**9.7 Common Acid-Base Reactions**

* **Neutralization reaction:** Acid + Base → Salt + Water.

**9.8 Titration**

* Used to determine the concentration of an acid or base.
* **End point:** Point at which the acid is neutralized.

**Quiz 9 (Chapter 9)**

**Question 1:** What is the conjugate base of HCl?

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<summary>Answer</summary>
Cl-
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**Question 2:** A solution with a pH of 9 is:

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<summary>Answer</summary>
Basic
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**Question 3:** Which of the following is a weak acid?

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<summary>Answer</summary>
H3PO4
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**Question 4:** The reaction of an acid with a base to produce salt and water is called:

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<summary>Answer</summary>
Neutralization reaction
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