2- Structures, properties and uses Flashcards
Ionic bonding?
metallic and a non metallic atoms that give (metal) and receive (non metal) electrons
Covalent bonding?
non-metallic atoms that share electrons
Ion?
Charged particles
Molecule?
A compound who’s atoms are covalently bonded
Metallic bond?
metallic atoms
loose all electrons on outer shell (become delocalised)
Bond because the positive atoms are held together by the strong attraction of the delocalised negative electrons holding the structure together
Delocalised electron?
Bonding electron that is no longer associated with a particular atom
What do carbon atoms form?
4 strong covalent bonds
When an electron is lost?
Becomes positive
When an electron is gained?
Becomes negative
What mass does each particle have? (P,N,E)
Protons- 1
Neutrons- 1
Electrons- negligible mass
What are isotopes?
An element with a different number of neutrons than normal, giving it a different relative atomic mass
How does melting and evaporating substances happen?
Using energy to break or lower the forces of attraction
What are intermolecular forces?
Weak forces of attraction between molecules (forces of repulsion)
What are intramolecular forces?
Strong forces of attraction holding together the atoms making up molecules or compounds
Why do simple covalent molecules have a low boiling point?
They have weak intermolecular forces which are easy to overcome using energy (does not break the covalent bond)
Why do ionic compounds have a high boiling point?
They have strong electrostatic charges and there are many atoms
What is nano science’s advantages and disadvantages?
Ad: can be used for unique things such as very efficient catalysts and new cosmetics and medically
Dis: if they are used to much, there is a theory that they could get into the air and our bodies and cause environmental or health issues
What are two key need to knows about nano particles?
They are one billionth of a metre
They have a large surface area to volume ratio (big surface area)