Unit 2: Antacids: Guided Notes: adapted from Kendall Hunt Chemistry You Need To Know
Section 2.1 Types of Matter
What is matter?
Pure Substance Mixture
Element CompoundHomogeneousHeterogeneous
Mixtures can be any combination of solids, liquids and gases:
Combination / ExampleSolid-Solid
Solid-Gas:
Solid-Liquid
Liquid-Liquid:
Gas-Liquid:
Gas-Gas:
True Solutions
- Particles do not settle out
- Particles are too small to scatter light
- Example:
Colloids:
- Particles do not settle out
- Particles are large enough to scatter light (Tyndall Effect)
- Example:
Suspension:
- Particles will settle out over time.
- Example:
Using the above information about true solutions, colloids, and suspensions, write them in order of Increasing particle size.
Making Connections
- Consider an antacid like Maalox®, Tums, ®or Mylanta®. Are they pure substances or mixtures?
- Antacids contain active ingredients and inactive ingredients. What purposes do inactive ingredients serve? List 4.
Complete the Chart by writing in the column on the left if the substance is an element, compound, homogeneous mixture or heterogeneous mixture.
Aluminum foilwater
a glass of soda
soil
Carbon dioxide
2.2: Naming Chemicals
The language of Chemistry includes element symbols, chemical formulas and chemical equations. Each element symbol starts with a capital letter.
Binary Ionic Compounds
Naming ionic compounds:
- Write the name of the cation first.
- For the name of the anion, the ending of the element name is changed to “ide”.
- Example: oxygen becomes oxide; sulfur becomes sulfide; fluorine become fluoride
Examples:
Na Br First element: cation:
Second element: anion:
Name of compound:
Ca Br First element: cation:
Second element: anion:
Name of compound:
K2O First element: Cation:
Second element: Cation:
Name of compound:
Now you try:
Complete the chart with the missing information.
Formula / 1st element / Cation name / 2nd element / Anion name / Compound nameCaF2
Na3P
NaCl
SrBr2
Polyatomic Ions: more than one atom that together have a charge.
Ternary Compounds: compound containing at least one polyatomic ion.
polyatomic ionic compound
(Your reference tables have a list of common polyatomic ions: you don’t need to memorize them.)
Identifying polyatomic ions
- The only cation (front-half) polyatomic ion is ammonium, NH4
- All other polyatomic ions are anions (written second in the formula)
- Several polyatomic ions have the same three elements but the number of oxygen atoms is different between them so the subscripts on the oxygen atom will be different. Be careful to choose the correct one.
- Example: sulfate SO4 and sulfite SO3
- If the formula contains parenthesis () the polyatomic ion is always inside the parenthesis.
You Try: Find the polyatomic ion in the following compounds using your polyatomic ions list:
NaNO3K2SO4Ca(OH)2(NH4)2S
Naming compounds with polyatomic ions
- There will be more than 2 capital letters (none starting with H)
- Write the name of the cation (the metal element or ammonium if cation is NH4)
- If the polyatomic ion is the anion, then name it just as it is on the list. You do not have to change the ending of a polyatomic ion to “ide”.
- If the anion is a single element and not a polyatomic ion, then the ending will change to “ide” .
- Sometimes a compound is composed of 2 polyatomic ions. For these, you name the first polyatomic ion followed by the name of the second.
Name the four compounds above for which you previously identified the polyatomic ion.
You Try: Practice naming the following compounds:
Ca(NO3)2
Na3PO4
NH4ClO
K2CO3
Naming ionic compounds when the metal is a transition or multi-valent metal.
- Multi-valent metals or the transition metals are metal elements that have more than one possible charge for the cation.
- Some of the most common multi-valent metals are copper, iron, nickel, lead,
- Write the name of the metal element (cation) first. Write the name of the anion. Don’t forget the ending “ide” if it’s a single element. Leave a small space between for a Roman numeral.
- To determine the Roman numeral to use, determine the total negative charge.
- Total negative charge = total positive charge for neutral compounds.
- Determine the charge of the metal ion.
- Write the charge in Roman numerals in parenthesis after the metal name.
Examples:
O
You try:
Name the following compounds with multi-valent cations.
PbCl2PbCl4MnOMn2O3
Covalent Compounds
Identifying and Naming Covalent Compounds
- These compounds have 2 elements
- Both elements are non-metal elements
- Write the name of the first non-metal with a prefix indicating the number of atoms. DO NOT USE the prefix “mono”.
(Including the “mono” prefix if there is only one atom) and the suffix “ide” as the ending.
Prefix / MeaningMono- / 1
di- / 2
tri- / 3
tetra / 4
penta- / 5
hexa- / 6
hepta- / 7
octa- / 8
nona- / 9
deca- / 10
Examples:
You try:
NO2CCl4 CO2
2.3 Writing Formulas for Chemical Compound
Writing formulas for Binary Ionic Compounds(metal element + non-metal element)
- Write the symbol and charge for the cation (metal).
- Write the symbol and charge for the anion (non-metal).
- The sum of all of the positive charge and all of the negative charge equals zero in a neutral atom.
- If the total charge is not equal to zero, you must adjust the number of cations or anion to create a neutral compound.
Note: Use your periodic table to help you determine the charges of most of the common cations and anions.
Examples: Sodium chloride Na = sodium cation with a 1+ charge
Cl= chloride anion with a 1- charge
Formula: NaCl
If we combined one of each ion we would write: NaCl. Adding up the charges would give an overall charge of zero since algebraically 1+-1 = 0. Since only one of each ion is needed we do not need any subscripts.
Calcium bromide Calcium symbol and charge:
Bromide symbol and charge:
#Ca needed: # of Br needed
Formula:
You try:
Compound name / Cation symbol / Cation charge / Anion Symbol / Anion charge / FormulaCesium chloride
Potassium oxide
Calcium sulfide
Lithium nitride
Writing formulas for Polyatomic Ionic Compounds
The same process is used as for binary ionic compounds except the anion will be a polyatomic ion that has its own charge. (The exceptions are ammonium NH4 and dimercury Hg2 which will be cations.)
- Write the symbol for the cation (or the polyatomic ion symbol if ammonium or dimercury).
- Determine the charge of the cation.
- Write the symbol of the anion or polyatomic ion.
- Determine the charge.
- Adjust the number of each ion so that a neutral compound is formed by adding subscripts to indicate how many of each ion are needed if more than one.
- If you need more than 1 of the polyatomic ions, you must place parenthesis around the formula for the polyatomic ion BEFORE you subscript it. The subscript goes outside the parenthesis. YOU DO NOT WANT 2 SUBSCRIPTS SIDE BY SIDE---MUST BE SEPARATED BY THE PARENTHESIS.
Examples:
Sodium carbonateNa (+1)CO3 (2-)
Need 2 sodium ions for each carbonate ion
Na2CO3
Magnesium nitrateMg (2+)NO3 (1-)
Formula:
You try:
Sodium nitrate
Calcium chlorate
Potassium sulfite
Calcium hydroxide
Writing formulas for compounds with multi-valent metals (transition metals)
The same rules apply as for the compounds above. The Roman numeral gives you the charge on the cation or multi-valent metal (transition metal).
Examples: Iron (III) oxide
Copper (II) nitrate
You try:
Iron (II) nitrate
Copper (I) chloride
Lead (Iv) hydroxide
Tin (II) oxide
Writing formulas for Covalent Compounds
- These compounds contain prefixes in their names. The prefixes indicate how many of each atom that you need. If there is not a prefix is it understood to be 1. YOU DO NOT HAVE TO WORRY ABOUT CHARGES FOR THESE.
Examples: dinitrogentetraoxide
Silicon dioxide
You try:
Carbon monoxide
Nitrogen dioxide
Dinitrogenpentoxide
NOTE: In chemistry “di” and “bi” prefixes do not refer to the same thing. Use “di” in naming compounds to indicate that 2 atoms are needed in a covalent compound. When “bi” is used in a name it means that the polyatomic ion contains a hydrogen atom.
2.4 Defining, Naming and Writing Acids and Bases
Arrhenius Acid
- Produce ______in water
- The hydronium ion is H+ and is a ______.
- According to the Arrhenius definition, if the acid gives a hydrogen to water, then all acids will contain hydrogen and it will be the ______(first element written).
Naming non-oxygen acids
- Start with “______”
- Do NOT contain______.
- Use “______”
- Fill in the ______with the ______name without the last syllable.
- Example: HBR
Naming Oxygen Acids (oxyacids)
- Start with “______”
- Contain ______
- Use “______” for “______” anions
- Use “ ______”for “______” anions
- Do ______use “______” with these……..acid in the name is how you know it begins with hydrogen
- Example: H2SO3
- Example: H2SO4
You try:
HCl
HNO3
H2S
H3PO4
Writing formulas for acids
- Acids with “hydro” in the name
- The cation is______.
- Write the symbol and ______.
- Write the symbol for the anion and find its charge.
- Balance the charges by adding ______to the hydrogen cation if needed.
- Example: Hydrofluoric acidformula:
- Acids without “hydro” in the name
- The cation is______.
- If it is an “______” acid, the anion is the “______” polyatomic ion.
- If it is an “______” acid, the anion is the” ______” polyatomic ion.
- Add ______to the hydrogen cation to ______.
- Example: Carbonic acid______nitrous acid______
You try:
Phosphoric acid
Hydroiodic acid
Carbonous acid
Perchloric acid
Arrhenius Base
- Produces ______in water
- Most bases are just ______with “______” as their ______.
- The most common exception to this is ______. It is a base even though it does not contain OH- as the ______.
- Example: NaOH
You try:
Ca(OH)2
KOH
Sr(OH)2
Copper(II)hydroxide
Magnesium hydroxide
Standard & Honors Chemistry