Chemical Bonding: Atoms, Molecules & Ions PDF

UNIT 4 ATOMS, MOLECULES & IONS Lesson 1: Atomic and Subatomic Structure Lesson 2: Ions and Molecules Lesson 3: Naming Compounds Carbon dioxide Sodium Chloride (NaCl) Hydrochloric acid (HCl) Acetic acid HOW ELEMENTS TURNED INTO COMPOUNDS? CHEMICAL BON...

UNIT 4 ATOMS, MOLECULES & IONS Lesson 1: Atomic and Subatomic Structure Lesson 2: Ions and Molecules Lesson 3: Naming Compounds Carbon dioxide Sodium Chloride (NaCl) Hydrochloric acid (HCl) Acetic acid HOW ELEMENTS TURNED INTO COMPOUNDS? CHEMICAL BONDING ⮚ Compounds are formed when elements are joined and held together by strong forces called chemical bonds. ⮚ Bonds are formed when valence electrons, the electrons in the outermost electronic “shell” of an atom, interact.  Oxidation Number/State ⮚ Electrons in the outermost or highest energy orbitals of an atom. ⮚ Enters into the formation of chemical bonds (gained/lost).  OCTET RULE ⮚ Refers to the tendency of atoms to prefer to have eight electrons in the valence shell. ⮚ When atoms have fewer than eight electrons, they tend to react and form more stable compounds. ⮚ A stable compound is one that is not very reactive in its environment or during normal use and keeps its useful properties for the expected amount of time. ⮚ Atoms become stable when their valence shell is full of electrons or when they satisfy the octet rule. ⮚ Atoms that don’t have eight valence electrons will try to reach it by gaining, losing, or sharing electrons thus forming a compound. OCTET RULE  NAMING OF CHEMICAL COMPOUNDS COVALENT BOND  COVALENT COMPOUND ⮚formed through Covalent Bond. ⮚formed as a result of sharing of electrons BETWEEN ANIONS (Non-Metals) to form chemical bonds. It is used in the manufacture of other It is used in the manufacture of other chemicals, in aluminum metallurgy, chemicals, in aluminum metallurgy, and in the pharmaceutical industry. and in the pharmaceutical industry.  BINARY COVALENT COMPOUND ⮚Greek prefixes are added to indicate the number of atoms of the element present in the chemical formula. ⮚The second element (anion) ends with the suffix –ide. ⮚The letter a is usually dropped when followed by a vowel, as in case of tetroxide, pentoxide and so on. ⮚The prefix mono- is not used on the first element in the formula. BINARY COVALENT COMPOUND BINARY COVALENT COMPOUND BINARY COVALENT COMPOUND  BINARY COVALENT COMPOUND ⮚ Some binary covalent compounds are not named systematically, but rather take trivial names/common names. BINARY COVALENT COMPOUND NO (laughing gas) Ammonia Solution IONIC BOND BOND  IONIC COMPOUND ⮚Is a result o attraction between CATIONS (metals) AND ANIONS (nonmetals). Due to an electrostatic attraction between charges. MgF2 - magnesium fluoride Fe2S3 - ferric sulfide  BINARY IONIC COMPOUND ⮚CRISS-CROSS METHOD ⮚ Done by using the numerical of the charge of one ion as the subscript for the opposite ion. ⮚ A subscript one (1) is not explicitly written in the formula. ⮚ Conversely, of the element in Barium Chloride formula does not have a subscript, the value is  BINARY IONIC COMPOUND ⮚With reducible subscript ⮚ If the formula ends up with reducible subscripts, then it is reduced to the simplest ratio. Lead IV Oxide / Plumbic Oxide  BINARY IONIC COMPOUND ⮚With reducible subscript Lead IV Oxide / Plumbic Oxide Pb+2 Lead II / Plumbous (lower) Pb+4 Lead IV / Plumbic (higher) O-2 Oxide (non-metal)  COVALENT IONIC NON-METAL + NON- METAL METAL + NON- METAL (ANION + ANION) (CATION + ANION) NO CRISS CROSS USE CRISS CROSS USE GREEK PREFIXES ROMAN NUMERALS / LATIN NAME FOR TRANSITIONAL METALS FIRST ELEMENT WITH 1 GROUP 1 AND 2 METAL = NO SUBSCRIPT = NO MONO- ROMAN NUMERALS ANIONS (NON-METALS) ALWAYS END IN –IDE BINARY IONIC COMPOUND