Flashcards in Particle Theory Deck (23)
What is covalent bonding?
Non-metal bonding by sharing electrons to gain stability
What are the diatomic molecules
What is a covalent bond?
The electrostatic attraction between the positive nuclei and the negative shared pair of electrons
What is simple molecular structure?
A regular arrangement of molecules held together by weak intermolecular forces
What are the properties of simple molecular structure?
1.low melting/boiling point (weak intermolecular forces)
2. Don't conduct electricity
What is giant covalent structure?
Adopted by the non-metals in group 4
Regular arrangement of ATOMS held together by strong covalent bonds
What are the properties of diamond?
1. V. high melting/boiling points
2. Electrical insulator
3. Extremely hard
What are the properties of graphite?
1. High melting/boiling point
2. Electrical conductor
What is an ion?
A charged atom or group of atoms
What is the ionic bond?
The electrostatic attraction between oppositely charged ions
What is giant ionic structure?
A regular lattice of alternating positive and negative ions
What are the properties of giant ionic structure?
1. High melting/boiling points (strong ionic bonds)
2. Often but not always soluble
3. Don't conduct electricity when solid but do in solution or as a liquid
What is a giant metallic structure?
A lattice of positively charged ions surrounded by a sea of delocalised electrons
What is the metallic bond?
The force of attraction between the delocalised outer electrons and the positive ions
What are the general properties of metallic structures?
1. Malleable - layers slide over each other
3. High melting/boiling points - strong metallic bonds.
4. Good conductors - free electrons
What is an isotope?
Atoms of the same atomic numbers but different mass numbers
How do you find the RAM including isotopes?
1. Multiply the mass by its real active abundance
2. Add them together
3. Divide by the sum of the relative abundances
How do you find the relative formula mass?
Add the atomic masses of each element in a molecule
How do you find the empirical formula?
1. Divide each percentage by molar mass
2. Divide the results by the smallest answer
3. This should turn into a ratio
How do you get the molecular formula of a molecule?
1. Divide the relative molecular mass by the mass of the empirical formula
2. Multiply the empirical formula by the answer
How do you calculate the masses in reactions?
1. Find the relative formula masses of the two molecules you want
2. Divide by the smallest one
3. Multiply by the given amount
How do you find the hydrated formula of a salt?
1. Work out the mass of each
2. Calculate the no. moles of water and salt you have
3. Work out the ratio