ionic bonds section 3. ion an atom or group of atoms that has become electrically charged
TRANSCRIPT
Ionic Bond Practice
• How many ions of magnesium and oxygen would you need to make an electrically neutral compound?– Mg– O
– What is the formula of the compound?
Ionic Bond Practice
• How many magnesium ions and iodine ions would you need to make an electrically neutral compound?– Mg– I
• What would be this compound’s formula?
Ionic Bond Practice
• How many phosphate ions and potassium ions would you need to make an electrically neutral compound?– Phosphate– Potassium
• What would be this compound’s formula?
Polyatomic Ions
• Many atoms• A group of atoms that react as one• Each polyatomic ion also carry either a
positive or negative charge– CO₃ (has an overall charge of -2)– This polyatomic ion functions as all ions. It is
attracted to ions that would have a overall charge to equal a +2. This would create a stable molecule.
Formulas for compounds
• Aluminum sulfide
• The metal scandium (Sc) has three valance electrons. What is the formula of the ionic compound formed when scandium reacts with iodine?
Naming Ionic Compounds• Name of positively charged ion
comes first, followed by the name of the negative ion.• If the negative ion is an element
– the end of the name changes to –ide.
Crystal Shape• Comes from the arrangement
of ions.• Ions are orderly and organized• Every ion is attracted to ions
near it that have an opposite charge.
High Melting Points
• Strong ionic bonds – difficult to break• When enough heat is applied – atoms speed
up. When they achieve enough energy the ions will overcome the attraction of the ionic bond and break free and change state.
• Table salt requires 801⁰C to melt.• This causes ionic compounds to be solids at
room temperature.
Electrical Conductivity• When dissolve in water, the solution conducts
electricity (the flow of electrons)• A solid ionic compound does not conduct
electricity• In a solid ionic compound – particles are in a fixed
position – electricity does not flow• When ions dissolve in water – ions move freely
and electrons will flow freely.• Melting ionic compounds allows electricity flow