Presentation on theme: "Ionic Bonding and Writing Formulas"— Presentation transcript:
1 Ionic Bonding and Writing Formulas Lesson 3.05Ionic Bonding and Writing Formulas
2 3.05 Ionic Bonding and Writing Formulas Watch the following video about ions:Then, draw a line from each word to its correct definition.IonAn atom or a group of atoms that form a charge by gaining or losing one or more electrons.Monoatomic IonAn ion that has a positive chargeTwo or more atoms bonded together. Can have an overall charge of positive or negative.Polyatomic IonAnionAn ion that has a negative chargeCationAn ion consisting of one element
3 Practice Determining Charge Watch the video about common charges:Download a periodic table with common charges here:What is the common charge for:a. Calcium: _____b. Phosphorus: ____c. Hydrogen: ____d. Sulfur: _____e. Aluminum: ____f. Iodine: ______
4 Let’s Write That Formula Ionic CompoundCation & Anion(+ is always written first)Overall charge of formula unit is zeroHow many ions of each element you need is its subscript
5 Ionic Compounds - Vocabulary Ionic Bonding – A chemical bond that is due to transfer of electrons between a cation (metal or H) and an anion (nonmetal).Ionic Compounds - A compound composed of positive and negative ions that are combined in a ratio where the positive and negative charges cancel out. Overall net charge is zero. The cation is always written first.Formula Unit - The formula of an ionic compound that represents the simplest whole number ratio of ions in the compound.
6 Writing Formula Units (Formulas) – The Basics Example: Write the formula when calcium and phosphorus bond.Write each ionThe positive ion is always written first, then the negative ion.Determine how many of each ion we need to make the compound neutral. That will be their subscripts.Subscripts must be the lowest whole number ratio.Check your workMake sure that the net charge of the formula is zero.
7 Writing Formula Units Practice Aluminum and PhosphorusCalcium and LithiumBromine and BariumNitrogen and Fluorine
8 Writing Formula Units – Criss-Cross & Reduce Method Write the formula that forms when the following pairs of elements form an ionic bond:Potassium and NitrogenHydrogen and oxygen3. Magnesium and sulfur4. Strontium and selenium
9 3.05 Comprehension Check What is the common charge of a magnesium ion? What is the formula that results when chlorine bonds with barium?Identify three atoms that would lose two electrons to empty its valence energy level.What subscripts are needed to complete the formula unit Al_N_?Which of the following forms a cation?Br b. Li C. NWhich of the following is a possible formula unit?KN3 b. I3N c. MgO
10 Thank You!It has been great working with you for Writing Ionic Compounds! You will use this for the rest of module 3, module 4 and most of segment 2.Please use our other recorded teaching sessions for the other lessons. Don’t forget that you can use them to review previous lessons too!