Writing Formulas!

All compounds and molecules are neutral. Ions have charges.

Bonding - a chemical attachment that forms a new substance. This new substance has new chemical and physical properties Example: Sodium is an explosive metal. Chlorine is a toxic gas. Sodium chloride is salt.

Metals Tend to lose e- Conductors Malleable and ductile

Nonmetals Tend to gain e- Non-conductors Brittle

Most common charges +3 variable charges (always positive) +2+1 ±40

Remember… Opposites attract

I. Bonds Ionic Bond- an exchange of electrons between a metal and a nonmetal. This creates oppositely charge ions that are attracted to each other.

- Losing e- forms a cation (+ ion) - Cats have paws - Cations are pawsitive -Gaining e- forms an anion (- ion) -Gaining e- forms an anion (- ion) -Onions make you cry -Anions are negative

I. Bonds B. Covalent Bonds - Formed by sharing electrons - Between two nonmetal atoms C. Metallic Bonds - Formed by a sea of electrons passing over the metal atoms - flexible connection, does not form a fixed molecule

II. Compounds A. Ionic Compounds - They only have two elements - the total amount of positive charge must equal the total amount of negative charge Compounds MUST be neutral

II. Compounds A. Ionic Compounds - subscripts are used to show how many of each element is needed to balance the overall charge

II. Compounds A. Ionic Compounds - the metal's name does not change - the nonmetal retains the root of its name and adds the suffix - ide

Sodium and Chlorine and 10- = 1+ Na and 18- = 1- Cl NaCl sodium chloride

Magnesium and Oxygen and 10- = 2+ Mg and 10- = 2- O MgO magnesium oxide

Magnesium and Chlorine 17+ and 18- = 1- Cl and 18- = 1- Cl and 10- = 2+ Mg MgCl 2 magnesium chloride

Ionic Nomenclature What is the formula for Na +1 and Cl -1 NaCl sodium chloride What are the symbols and charges? How many of each atom is needed to make the compound neutral?

Ionic Nomenclature What is the formula for Na +1 and O -2 Na 2 O sodium oxide What are the symbols and charges? How many of each atom is needed to make the compound neutral?

Ionic Nomenclature What is the formula for Al +3 and Cl -1 AlCl 3 aluminum chloride What are the symbols and charges? How many of each atom is needed to make the compound neutral?

Ionic Nomenclature What is the formula for Al +3 and O -2 Al 2 O 3 aluminum oxide What are the symbols and charges? How many of each atom is needed to make the compound neutral?

II. Compounds - the formula of an ionic compound must be in the lowest whole number ratio of the two elements to form a neutral compound (empirical formula) A. Ionic Compounds

Ionic Nomenclature What is the formula for Mg +2 and O -2 MgO magnesium oxide What are the symbols and charges? How many of each atom is needed to make the compound neutral?

II. Compounds - metals with variable charges must include the charge in the name using Roman numerals A. Ionic Compounds

Ionic Nomenclature What is the formula for Pb +2 and O -2 PbO lead (II) oxide What are the symbols and charges? How many of each atom is needed to make the compound neutral?

Ionic Nomenclature What is the formula for Mn +4 and O -2 MnO 2 manganese (IV) oxide What are the symbols and charges? How many of each atom is needed to make the compound neutral?

Ionic Nomenclature What is the formula for Cu +2 and N -3 Cu 3 N 2 copper (II) nitride What are the symbols and charges? How many of each atom is needed to make the compound neutral?

II. Compounds Polyatomic ions- a group of covalently bonded atoms with an overall charge that react as a group A. Ionic Compounds 2. Polyatomic ion Compounds

Ionic Nomenclature What is the formula for Cu +2 and SO 4 -2 Cu SO 4 copper (II) sulfate What are the symbols and charges? How many of each atom is needed to make the compound neutral?

Ionic Nomenclature What is the formula for Na +1 and SO 4 -2 Na 2 SO 4 sodium sulfate What are the symbols and charges? How many of each atom is needed to make the compound neutral?

II. Compounds If more than one polyatomic ion is needed to make a neutral compound, you must use parenthesis to group the ion. A. Ionic Compounds 2. Polyatomic ion Compounds

Ionic Nomenclature What is the formula for Ba +2 and OH -1 Ba(OH) 2 barium hydroxide What are the symbols and charges? How many of each atom is needed to make the compound neutral?

Ionic Nomenclature What is the formula for Al +3 and SO 4 -2 Al 2 (SO 4 ) 3 aluminum sulfate What are the symbols and charges? How many of each atom is needed to make the compound neutral?

Nonmetals Tend to gain e- Nonconductor Brittle

II. Compounds Nonmetals want to gain electrons. When two nonmetals are together, they share the electrons. B. Covalent (Molecular) Compounds

Hydrogen and Hydrogen H H2H2 H

Nitrogen and Hydrogen (Ammonia) H H H N NH 3

Hydrogen and Oxygen H2OH2O H H O

II. Compounds Naming covalent compounds - Because covalent compounds may form different compounds between two nonmetals with different ratios, the subscripts are denoted in the name by a prefix.

Covalent Nomenclature 1 mono 2 di 3 tri 4 tetra 5 pent 6 hex 7 hept 8 oct 9 non 10 dec

II. Compounds Naming covalent compounds - The element on the left will go first in the name. - The element on the right will go last in the name. The root remains the same, but the suffix –ide is added. - The prefix in front of each element give the number of atoms (subscript written behind.)

Covalent Nomenclature What is the formula for 1 carbon 1 oxide CO carbon monoxide

Covalent Nomenclature What is the formula for 1 carbon 2 oxide CO 2 carbon dioxide

Covalent Nomenclature What is the formula for 2 phosphorus 5 oxide P2O5P2O5 diphosphorus pentoxide

Is it covalent or ionic? Covalent - Look for prefixes (except dichromate) - 2 nonmetals - prefixes become subscripts - Remember these are the easy ones. No charges! No crisscross! Ionic - metal & nonmetal or metal & polyatomic - write the symbol and charge - balance charges to form a neutral compound (crisscross) - check to make sure you have the lowest whole number ratio!

Write the formulas for these lithium permanganate tetraiodide monoxide tin (II) oxide tin (IV) oxide diphosphorus pentoxide aluminum dichromate tetrasulfur hexaphosphide

Write the names of the following: KCl Cl 2 O 7 CuSO 3 CO 2 CrN NaNO 3 Sb 2 S 3

Write the formulas for these nitrogen trioxide magnesium cyanide copper (II) hydroxide carbon tetrafluoride iron (III) bicarbonate manganese (IV) chlorite iron (III) carbonate

Write the names of the following: BaCl 2 CaSO 4 (NH 4 ) 2 O LiCN Fe(OH) 3 Na 3 N NiPO 4

Write the names of the following: N 2 O NO 2 PbO PbO 2 Na 2 S CBr 4 (NH 4 ) 2 CO 3

II. Compounds The anion changes its suffix: -ate converts to -ic acid -ite converts to -ous acid -ide converts to hydro--ic acid C. Acids - (Special Ionic Compounds) 3. Acids- ionic compounds that start with H +1 plus an anion

II. Compounds You –ate something and it made you s–ick, and you mite give it to -ous. C. Acids - (Special Ionic Compounds) 3. Acids- ionic compounds that start with H +1 plus an anion

Acidic Nomenclature What is the formula for H +1 and Cl -1 HCl hydrochloric acid What are the symbols and charges? How many of each atom is needed to make the compound neutral?

Acidic Nomenclature What is the formula for H +1 and SO 3 -2 H 2 SO 3 sulfurous acid What are the symbols and charges? How many of each atom is needed to make the compound neutral?

Acidic Nomenclature What is the formula for H +1 and SO 4 -2 H 2 SO 4 sulfuric acid What are the symbols and charges? How many of each atom is needed to make the compound neutral?

Acidic Nomenclature What is the formula for H +1 and CrO 4 -2 H 2 CrO 4 chromic acid What are the symbols and charges? How many of each atom is needed to make the compound neutral?

Write the names of the following: HBr H 2 SO 4 H 3 PO 4 HNO 2 HC 2 H 3 O 2 H 2 CO 3

Write the formulas for these chloric acid sulfurous acid chromic acid hydrophosphoric acid carbonic acid hydroiodic acid