Bonding, Structure and the properties of matter Flashcards
Ionic, covalent, metallic bonding, polymers, diagrams, formulae, particle model,
What are the three types of chemical bond?
-Ionic
-Covalent
-Metallic
What are the particles in ionic bonding?
Oppositely charged ions
What are the particles in covalent bonding?
Atoms which share pairs of electrons
What are the particles in metallic bonding?
Metal atoms which share delocalised electrons
Where does ionic bonding occur?
Compounds formed from metals combined with non-metals
Where does covalent bonding occur?
Most non-metallic elements (including the halides) and in compounds of non-metals
Where does metallic bonding occur?
In metallic elements and alloys.
What is an ion?
A charged particle.
What type of elements lose electrons from their outer shell to form positive ions?
Metals
What type of elements gain electrons into their outer shell to form negative ions?
Non-metals
Which group in the periodic table do ions (produced by metals in group 1 and 2 and non metals in groups 6 and 7) resemble/have the electronic structure of?
The noble gases (group 0) because they have a full outer shell.
What does the ending ‘ide’ indicate?
That a non-metal is a negative ion (anion)
What should you do when drawing a dot and cross diagram?
-Only draw the outer shells
-Don’t draw the circles
-Dots represent electrons on the metal
-Crosses represent electrons on the non-metal
How do you draw a dot and cross diagram?
-Draw the elemental symbol for each element (e.g. K + I)
-Draw dots around one and crosses around the other to show the electrons on the outer shell only
-Draw an arrow
-Draw the elemental symbols again
-Draw the new electron configuration on the outer shell of the non-metal (with dots to show which electrons have been transferred)
-Draw square brackets around each
-Write the charge of the ion on the top right hand corner outside the bracket
-Write the electron configuration (so how ALL the electrons are arranged) in normal brackets underneath EVERY elemental symbol.
Written explanation for ionic bonding
- …atom loses …electron(s) to become a … ion.
2….atom gains…electron(s) to become a…ion.
- The two ions now have a full outer shell
- They are strongly attracted to one another by electrostatic forces so form an ionic bond (as they are oppositely charged).
- …(name the compound) something ‘ide’ is formed.
What is an empirical formula?
A formula that shows the elements in a compound in their simplest whole-number ratio.
Charges on ions in a compound must…
balance
Why do compounds such as Na₂O have elements reacted in a 2:1 ratio?
The metal ion has a 1+ charge but the non-metal ion has a 2- charge. The charges must balance.
What will ionic compounds look like?
Crystals.
Are Ionic compounds soluble?
Yes, they can become an aqueous solution because ions are charged and attracted to water molecules.
What do electrostatic forces of attraction do? (in terms of bonding)
Hold ions together in an ionic lattice
Why can ionic compounds conduct electricity when molten or aqueous, but not when solid?
-When solid, ions are fixed in the lattice so cannot move.
-Ions in the molten or aqueous state are free to move and carry a charge. (charge can flow)
How can we represent ionic compounds?
-Dot and cross diagrams
-Ball and stick models
-2D diagram
-3D diagram
What is an ionic lattice?
A giant, regular structure of ions held together by electrostatic forces of attraction in all directions between the oppositely charged ions.