CC5-7 Essentials Flashcards
What type of elements will form a covalent bond?
non-metal with non-metal
What type of elements will form an ionic bond?
non-metal with metal
What type of elements will form a metallic bond?
metal with metal
What type of bond will a non-metal form with another non-metal?
covalent
What type of bond will a metal form with another metal?
metallic
What type of bond will a non-metal form with a metal?
ionic
Describe a covalent bond
atoms share pairs of electrons
Describe an ionic bond
atoms gain or lose electrons to form ions which are attracted to each other by a strong electrostatic forces
Describe a simple molecular, covalent substance
Atoms are joined by strong covalent bonds to form molecules. The molecules attracted to other molecules by weak intermolecular forces.
What type of substance is water?
simple molecular
Why are simple molecular substances liquids or gasses at room temperature?
Simple molecular substances melt at boil at low temperatures because it does not take much energy to overcome the weak intermolecular forces between molecules
Why can’t simple molecular substances conduct electricity?
because they don’t have any electrons or ions which are free to move
Why do ionic substances have high melting and boiling points?
It takes a lot of energy to overcome the strong electrostatic forces holding ions together
What state can ionic substances conduct electricity in?
As liquids (molten) or when dissolved (in solution / aqueous)
What state can’t ionic substances conduct electricity in?
As solids
Why can ionic substances conduct electricity when molten or in solution but cannot when solids?
As solids the ions cannot move around but when molten or in solution the ions can move around
Describe the structure of diamond. (What element is it made from? What type of bonds form? How many bonds does each atom make?)
Diamond is formed from carbon atoms which each have 4 covalent bonds to other carbon atoms
Melting and boiling requires bonds to be broken
Why is diamond so strong and have such a high melting and boiling point?
Because each atom has 4 strong covalent bonds to other carbon atoms so it takes a lot of energy or a large force to break.
Describe the structure of graphite. (What element is it made from? What type of bonds form? How many bonds does each atom make? What happens to carbon’s 4th outer shell electron?)
Graphite is formed from carbon atoms which each have 3 covalent bonds to other carbon atoms. Each carbon’s 4th outer shell electron becomes a delocalised electron.
Why can graphite conduct electricity?
because 1 outer shell electron from each carbon becomes delocalised
