Bonding structures Flashcards
What is a molecule?
2 or more (non-metal ) atoms held together by covalent bonds
What is meant by a diatomic molecule?
( L.O. 20)
A molecule made up of 2 atoms
What are the 7 elements that exist as diatomic molecules?
( L.O. 20)
What is a covalent bond?
( L.O.17)
A shared pair of electrons
Why do elements take part in reactions?
( L.O.19)
To achieve a full outer shell and achieve a noble gas electron arrangement.
What type of elements form covalent bonds?
( LO : 18 )
Non - metal elements
What holds the atoms together when they form covalent bonds?
( LO : 17 )
The common (electrostatic) attraction the nuclei have for the shared pair of electrons.
How do non-metal atoms achieve a full outer shell when they react with one another?
( L.O.19)
They share unpaired electrons
What 4 shapes of molecules must we know?
( L.O 21)
What are the properties of covalent molecular substances?
( L.O. 24)
Why do covalent molecular substances have low melting and boiling points?
( L.O. 24)
Are covalent molecular substances soluble in any other liquids?
( LO 25 )
Yes. Hexane for example
What are the properties of covalent network substances?
( LO 26 )
Why do covalent network substances have high melting and boiling points?
( LO 26 )
Why do covalent network substances NOT conduct electricity?
Because the charged particles ( electrons) are NOT free to move.
What is an ion?
An atom that has lost or gained electrons
Why do atoms form ions?
To obtain a full ( stable) outer shell
How does an ionic bond form?
An electrostatic attraction forms between oppositely charged ions
What name do we give to the structure an ionic solid takes?
Do ionic compounds have high or low melting and boiling points?
Why are many ionic compounds soluble in water?
The attractions that polar water molecules have for ions tears the lattice apart
Do ionic compounds conduct electricity?
Solid: No
Liquid: Yes
Solution : Yes
