Presentation on theme: "1 The Structure of Matter Chapter 5. 2 Compounds Compounds are made from two or more elements. The compound has properties that are different from."— Presentation transcript:
2 Compounds Compounds are made from two or more elements. The compound has properties that are different from those of the elements that make it. Compounds always have the same chemical formula.
3 Chemical Bonds The attractive forces that hold different atoms or ions together in compounds are called chemical bonds. A bond length gives the distance between the nuclei of the two bonded atoms. Bond angles tell how these atoms are oriented in space.
4 Structural Formulas Structural formulas can show how the atoms are arranged in a compound.
5 What do we call the force that holds atoms in a molecule together? 1. Atoms 2. Chemical bond 3. Nucleus 4. Valence electrons
6 The properties of a compound are different than the properties of the elements that make up the compound. 1. True 2. False
7 Types of Bonds Ionic bonds are formed between oppositely charged ions. Metallic bonds are formed between atom’s nucleus and a neighboring atom’s electrons. Covalent bonds are made between atoms of nonmetals.
8 Ionic Bond Bond between a metal ion and a nonmetal ion. The oppositely charged ions are attracted to each other. Forms ionic solids. High melting point. Conduct electric current.
9 Metallic Bond Bond that occur between atoms of metal. Compounds are malleable and ductile. Conduct electricity & heat. Mixed to form alloys.
10 Covalent Bond Bond formed between two nonmetals. Share electrons. Lower melting and boiling points than ionic compounds. Covalent compounds are soft and squishy. Covalent compounds tend to be more flammable than ionic compounds.
11 Polyatomic Ions Polyatomic ions are groups of covalently bonded atoms that have either lost or gained electrons. The group of atoms act as a single ion. Polyatomic ions are put in parenthesis when you need to have more than one in a ion. HCO 3 −
12 Writing Chemical Formulas for Ionic Compounds List the symbols for each ions. Write the symbols for the ions with the cation first. Find the least common multiple of the ions’ charges. Write the chemical formula, indicating with subscripts how many of each ion are needed to make a neutral compound.
13 Naming Covalent Compounds Name the element that is farthest to the left on the periodic table. Add a prefix if there is more than one atom. Name the element that is farthest to the right on the periodic table and change the ending to an –ide.
14 Writing Chemical Formulas for Covalent Compounds. List the chemical symbols of the elements. Add subscripts to indicate how many atoms of each element there is in a molecule of the compound. CO 2
15 Empirical vs. Molecular Formulas Empirical formula shows the smallest whole-number ratio of atoms that are in a compound. Molecular formula tells how many atoms are in one molecule of the compound. C 6 H 12 O 6
16 Organic Compound Organic compound is a covalently bonded compound made of molecules. Organic compounds contain carbon and most of the time hydrogen. Carbon can form four covalent bonds. Compounds made of only hydrogen & carbon atoms are called hydrocarbons.
17 Types of Organic Compounds Alkanes only have single covalent bonds. Alkenes have double covalent bonds. Alcohols have hydroxly or –OH group attached.
21 Polymers Polymers are large molecule that is formed by more than five monomers or small units. Polymers can be natural or synthetic. Polymers elasticity varies depending on the structure.
22 Biochemical Compounds Biochemical compounds are naturally occurring organic compounds that are very important to living things. Type of biochemical compounds: Carbohydrates (simple sugars) Proteins (amino acids) Lipids (fatty acids)