Chapter 13 Chemical Compounds

Chemical Compounds Introduction In Chapter 12, we learned how to balance chemical reaction containing elements and chemical compounds. In Chapter 13, we will learn about the structure and properties of ionic and covalent compounds as well as the properties of acids and bases. Acids and bases are found in things that we encounter everyday.

Chemical Compounds Introduction 1) What is a chemical compound? 2) What is an ionic compound? 3) What is a covalent compound? 4) How does bonding occur in atoms?

Chemical Compounds Introduction 5) What is an acid? 6) What is a base? 7) What is a substance with a high acid content? 8) What is a substance with a high base content?

Section 1: Objectives 1) Describe the properties of ionic and covalent compounds. 2) Classify compounds as ionic or covalent based on their properties.

Ionic and Covalent Compounds When ions or molecules combine, they form compounds. A chemical bond is the combining of 2 atoms to form molecules or compounds. Bonding can occur between valence electrons of different atoms. This is how chemical bonds are made.

Ionic and Covalent Compounds An ionic bond is an attraction between oppositely charged ions. Compounds that contain ionic bonds are called ionic compounds. Ionic compounds are: Brittle Have a high melting point Soluble

Ionic and Covalent Compounds Brittleness is a property that most ionic compounds share. Ionic compounds tend to be brittle solids at room temperature. They usually break apart when hit.

Ionic and Covalent Compounds

Ionic and Covalent Compounds High melting points are another property that ionic compounds share. Ionic compounds have a high melting point because of the strong ionic bonds that hold ions together. In other words, it takes a lot of heat/energy to break an ionic bond.

Ionic and Covalent Compounds Ionic compounds are highly soluble. They dissolve easily in water. They are good conductors of electricity because the particles left are charged. Ionic compounds are highly soluble and very ductile.

Ionic and Covalent Compounds Covalent compounds are compounds that form when a group of atoms shares electrons. This sharing of atoms forms a covalent bond. Covalent bonds are weaker than ionic bonds.

Ionic and Covalent Compounds Covalent Bond Properties: Low Solubility Low Melting Points Not good conductors of electric current

Chapter 13 Section 1: Recap 1) What must happen before compounds can form? 2) What is an ionic bond? 3) Give 3 properties of ionic compounds. 4) What is required before an ionic compound can break?

Chapter 13 Section 1: Recap 5) T/F Covalent bonds are stronger than ionic bonds. 6) List 3 properties of covalent bonds. 7) Ionic compounds are ________ ________ and very _________.

Chapter 15 Section 1-2: Recap 8) List 3 properties of acids. 9) List 3 properties of bases. 10) List 1 common use for an acid and 1 common use for a base.

Section 2: Objectives Describe 4 properties of acids. Identify 4 uses of acids. Describe 4 properties of bases. Identify 4 uses of bases.

Acids and Bases Acid: any compound that increases the number of hydronium ions when dissolved in water Hydronium ion: H30+

Acids and Bases There are 4 properties of acids: Sour flavor Change color in indicators React with metals Conduct electricity Indicator: compound that can reversibly change color depending on pH conditions

Acids and Bases These are some uses of acids: Sulfuric acid is used to make products such as paper, paint, detergents, and fertilizers. Hydrochloric acid is used to make cleaner for swimming pool liners. Citric acid and ascorbic acid are found in orange juice.

Acids and Bases Base: any compound that increases the number of hydroxide ions when dissolved in water Hydroxide ion: OH-

Acids and Bases There are 4 properties of bases: Bitter flavor Change color in indicators Conduct electricity Slippery feel

Acids and Bases These are some uses of bases: Sodium hydroxide is a base used to make soap and paper. Calcium hydroxide is used to make cement and plaster. Ammonia is found in many household cleaners.

Section 3: Objectives Explain the difference between strong acids and weak acids. Explain the difference between strong and weak bases. Identify acids and bases by using the pH scale. Describe the formation and uses of salts.

Solutions of Acids and Bases Acid: any compound that increases the number of hydronium ions when dissolved in water Hydronium ion: H30+ Base: any compound that increases the number of hydroxide ions when dissolved in water Hydroxide ion: OH-

Solutions of Acids and Bases Acids and bases can be strong or weak. The strength of an acid or base depends on the number of molecules that break apart when dissolved in water. When measured, the number of hydronium (acid) or hydroxide (base) atoms in water determines the strength of the acid or base.

Solutions of Acids and Bases Acids and bases can have different concentrations as well. The concentration of an acid or base is the amount of dissolved in water. Strong acids: Sulfuric acid, nitric acid, hydrochloric acid. Weak acids: Acetic acid, citric acid, carbonic acid.

Solutions of Acids and Bases The reactions between acids and bases are neutralization reactions. Acids and bases neutralize one another because the hydrogen (H+) and hydroxide ions (OH-) react to form water, which is neutral. If the water evaporates, the remaining ions join to form a salt compound.

Solutions of Acids and Bases An indicator determines if a solution contains an acid or a base. The pH scale is used to determine how acidic or basic the solution is. The pH of a solution is a measure of the hydronium ion concentration in the solution.

Solutions of Acids and Bases A salt is an ionic compound formed from the positive ion of a base and the negative ion of an acid. Organic compounds are any compound that contains carbon. The carbon elements work as a back-bone for the compound.

Chapter 15 Sec. 3 Recap 1) What is the difference between the strength and concentration of an acid or base? 2) Explain one way that water is formed. 3) What is the pH scale used for? 4) What are organic compounds? 5) What is the function of the carbon atoms in an organic compound?

Thinking Outside the Box You have been assigned to design a test that would determine the most productive type of chemical additive for plants. You have been given three different chemical additives and are required to design an experiment to determine which increases plant growth the most. You have access to any materials needed to complete the experiment.

Thinking Outside the Box Testable Question: Which chemical additive will yield the greatest plant growth? Hypothesis: (This is your educated guess.) Experiment: Design an experiment to test your hypothesis. Independent Variable: Changes for each experiment. Dependent Variable: What is measured during the experiment?

Thinking Outside the Box Controls: What stays the same for each test in the experiment? Results: Select a type of graph or chart you will use to display your results and explain why you chose that type of graph. (Bar graph, pie chart, data table, etc.) Conclusions: Explain why your results.

Chapter 13 Vocabulary Review ________: a mixture in which the substances are not evenly mixed ________: another name for homogeneous mixture ________: the substance that exists in the greatest quantity in a solution ________: the amount of a particular solute in a given amount of a solution ________: a molecule with a slightly negative end and a slightly positive end

Chapter 13 Vocabulary Review 6) ________: a solution that can still dissolve more solute at a given temperature and pressure 7) ________: a substance that produces hydroxide ions (OH-) when dissolved in water 8) ________: an inverse measure of the concentration of hydronium ions (H30+) in a solution 9) ________: the maximum amount of solute that can dissolve in a given amount of solvent at a given temperature and pressure

Chapter 13 Vocabulary Review 10) _______: all other substances in a solution (other than the solvent) 11) _______: 2 or more substances that are physically blended but not chemically bonded 12) _______: a mixture in which 2 or more substances are evenly mixed on the atomic level but not bonded together 13) _______: matter that is always made up of the same combination of atoms

Chapter 13 Vocabulary Review 14) _______: a solution that contains the maximum amount of solute the solution can hold at a given temperature and pressure 15) _______: a substance that produces hydronium ions (H3O+) when dissolved in water 16) _______: a positively charged ion formed when an acid dissolves in water 17) _______: a compound that changes color at different pH values when it reacts with acidic or basic solutions