Bonding Flashcards
What is ionic bonding?
- in ionic bonding, atoms lose or gain electrons to form charged particles called ions, which are then strongly attracted to one another (because of the attraction of opposite charges).
- this strong attraction is known as electrostatic attraction: it gives ionic compounds their high melting and boiling points
What is oxidation?
- when an atom loses electrons
What is reduction?
- when an atom gains electrons
Which groups of elements most readily form ions and why?
- groups 1, 2, 6 and 7
- their shells are nearly full or only have 1 or 2 electrons in the outer shell
What are cations and which groups of elements become them?
- positively charged ions
- groups 1 and 2 as they lose electrons
What are anions and which groups of elements become them?
- negatively charged ions
- groups 6 and 7 as they gain electrons
What happens when the cations collide with the anions?
- they attract each other to form an ionic compound
Why can only elements of opposites sides of the periodic table form ionic compounds?
- because one of them becomes a cation and the other an anion
- therefore, it’s between a metal and non-metal
What do compounds with ionic bonding always have?
- giant ionic structures
What is the structure of giant ionic structures?
- ions are held together in a closely packed 3D lattice arrangement by the attraction between oppositely charged ions
Describe the electrostatic attraction between the oppositely charged ions
- very strong
What are the properties of ionic compounds?
- high melting and boiling point
- brittle
- conduct electricity when molten or in solution, but not as a solid
Why do ionic compounds have high melting and boiling points?
- a lot of energy is needed to overcome the strong electrostatic attraction.
Why are ionic compounds brittle?
- if you hit it, ions of the charge move to become adjacent to each other
- so they repel
Why do ionic compounds only conduct electricity when molten or in solution?
- in a solid, ions are held in a lattice, so are not free to move
- in molten or solution, ions are free to move