Physical Science

Physical Science Chapter 6: Compounds Ionic and Covalent Compounds

Physical Science:Chapter 6, Compounds Chemical Bonds • A _____________is a substance made of two or more elements chemically combined (bonded together). • The forces that hold atoms or ions together are called _________________.

Physical Science:Chapter 6, Compounds Chemical Formulas • A compound can be represented by a __________________, like CO2 • The chemical formula tells you ______________________________and the ______________________.

Physical Science:Chapter 6, Compounds Chemical Structures • A __________________is aMODEL that shows you the elements in a compound, the ratios of the elements AND ______________________________

Physical Science:Chapter 6, Compounds Chemical Structures & Properties • The structure of a compound determines the _____________________________________ of the compound. color viscosity flammability

Physical Science:Chapter 6, Compounds Chemical Structures & Bonding • Usually atoms combine to form compounds so that each atom will have _________________________ ______________________________________________________________

Physical Science:Chapter 6, Compounds Chemical Bonding There are two basic types of chemical bonding • ______________________ • ______________________ We will also briefly cover • __________________________ • ____________________

Physical Science:Chapter 6, Compounds Chemical Bonding: Ionic Bonding • Ions are _________________. • Ions are formed when atoms transfer _______________. • __________are negative ions and _____________ are positive ions.

Physical Science:Chapter 6, Compounds Chemical Bonding: Ionic Bonding • ___________________are formed when cations andanionsare attracted to each other. • Since__________formcations and_________formanions,many ionic compounds are made of ________ions and __________ions, like Na+ &Cl- to form NaCl.

Physical Science:Chapter 6, Compounds Properties of Ionic Compounds • ________________________________ Ionic bonds are fairly strong so that ionic compounds • ________________________________ • ________________________________ • ________________________________

Physical Science:Chapter 6, Compounds Chemical Bonding: Covalent Bonds • _____________atoms (except the Noble Gases) do NOT have“enough”________ electrons (short of an octet) • If non-metals are surrounded by other non-metal elements, they can’t transfer electrons, so they will ________________electrons in _______________________.

Physical Science:Chapter 6, Compounds Chemical Bonding: Covalent Bonds • Sometimes non-metals atoms only need to share a pair of electrons. One shared pair = _________ covalent bond. • ____shared pairs = a __________bond • ____shared pairs = a __________bond • Covalently bonded units are known as molecules.

Physical Science:Chapter 6, Compounds Chemical Bonding: Covalent Bonds • When two atoms of the same element form covalent bonds by sharing electrons, they share electrons __________________, so the bond is a_____________________covalent bond. • When there is _______________sharing of electrons, it is called a __________ covalent bond.

Physical Science:Chapter 6, Compounds Chemical Bonding: Covalent Networks • _______________________________are very strong covalent bonding situations over _______atoms instead of just a pair of atoms. • Non-metals in covalent networks form some of the ____________substances known. • Examples of Carbon Networks: 1____________________2__________________ 3____________________

Metallic Bonds • ___________that are in elemental form or bonded together have a special kind of arrangement of nuclei surrounded by valence electrons that are ___________________. • This is often referred to as an “_______________” model or “_____________________” • The electrons are said to be “______________”. • It is believed that this special arrangement gives metals the properties that they possess, such as: • __________________________________ • ____________________ • ____________________

Physical Science Chapter 6: Compounds Naming Ionic and Covalent Compounds

Physical Science:Chapter 6, Compounds Ionic Compound Formulas • Ionic compound formulasshow the ratio of elements in an ionic compound. • For example: • The chemical formula BaCl2shows that there are two chloride ions for each barium ion in a barium chloride crystal.

Physical Science:Chapter 6, Compounds Ionic Compound Formulas • A single crystal of table salt has billions of ions in a crystal network so its formula could be: Na100,000,000,000 Cl100,000,000,000 • We use the lowest whole number ratio for the ionic formula, so the ionic compound formula isNa1Cl1 (NaCl) • This is known as an empirical formula.

Physical Science:Chapter 6, Compounds Ionic Compound Formulas • Ionic compound formulas have to “balance.” • They must have the same number of positives (+’s) as negatives (–’s) in the total formula (total equal to zero) • Examples: Na1+Cl1- (1+ and 1-) = 0 Ba2+S2- (2+ and 2-) = 0

Physical Science:Chapter 6, Compounds Covalent Molecule Formulas: • Molecular formulas are NOT just ratios like the empirical formulas for ionic compounds. • Molecular formulas state EXACTLY how many atoms of each element are in the molecule. Example: Glucose (C6H12O6)has: 6 carbon, 12 hydrogen & 6 oxygen atoms

Physical Science:Chapter 6, Compounds Covalent Molecule Formulas: • There are millions of compounds made with covalent bonds. • In Physical Science we will only deal with the formulas and names of the simplest types. • In this Chapter we will learn formulas and names for binarymolecules

Physical Science:Chapter 6, Compounds Covalent Molecule Names: • These compounds will contain two nonmetals • For binary covalent molecules’ names: a). List the elements in the compound b). Say how many of each element are in the compound.

Physical Science:Chapter 6, Compounds Covalent Molecule Names: • To say the number of atoms, chemists use the following numbering system: mono = 1 hexa = 6 di = 2 hepta = 7 tri = 3 octa = 8 tetra = 4 nona = 9 penta = 5 deca = 10 *Note: “mono” is not usually used for the first element in a covalent compound.

Physical Science