Chemistry Flashcards
What are orbitals?
Electrons dont have the same amount of energy and so they are broken down into subshells called orbitals/
What is the orbital order?
1s, 2s, 2p 3s, 3p,4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f
Describe electrons in terms of spin
Two possible states- ‘spin up’ and ‘spin down’ Each electron has a different spin state
Describe electrons in terms of spin
Two possible states- ‘spin up’ and ‘spin down’ Each electron has a different spin state
Define a positve and negative charge
Positive- When an atom loses electrons
Negative- When an atom gains electrons
What is electrostatic attraction?
The force experienced by oppositely charged particles. It holds the particles strongly together
What is ionic bonding?
- When an atom loses one or more electron and donates it to another.
- Between metals (losing) and non-metals (gaining)
What is covalent bonding?
- Occurs between two non-metals
- A covalent bond forms when an electron is shared between the atoms
What is an organic compound?
A compound that contains one or more carbons in a carbon chain
What is a lone pair?
`A non-binding pair of electons
What is metallic bonding?
- The sharing of free electrons among a structure of positively charged ions
- Between two metals
- Electrons move in a ‘sea’ of electons
What is a non-polar molecule?
A molecules where the electrons are distributed evenly throughout the molecule
What is a polar molecule?
A molecule with partial positive charge in one part of the molecule and a similar negative charge in another part due to uneven electron distribution
What is electronegativity
The tendacy of an atom to attract a bonding pair of electrons. Atoms that have similar electronegativities form covalent bonds.
What are the two types of covalent bonding?
Polar and non-polar covalent bonding
What are intermolecular forces?
The attraction or repulsion between neighbouring molecules. All of the attractions are called Van der Waals forces
What are london dispersion forces?
- London dispersion forces are a type of force acting between atoms and molecules that are normally electrically symmetric
- Weakest force
What are dipole-dipole forces?
-Dipole-dipole forces are attractive forces between the positive end of one polar molecule and the negative end of another polar molecule
What is hydrogen bonding?
- Strongest force
- When there is an attraction between the positive end of one and the lone pair of electrons on the other.
What is the equation for molar mass
Molar mass= mass/number of moles
What is a mole?
1 mole= 6.022 x 10 to 23
How to work out the relative formula mass?
The total sum of all the relative atomic masses
What is the relative atomic mass?
Tells you how much mass there is in one mole of the element
What is the empirical formula?
The ratio between elements in a chemical compound
What is the molecular formula?
To work it out you need the relative molecular mass and the empirical formula.
How do you work out the number of moles?
Number of moles= Molarity x volume of solution N=CV
What is titration?
A method of volumetric analysis used to calculate the concentration of a solution
Ho do you work out percentage yeild?
actual mass/theoretical mass x100%
What are cations and anions?
Cations- Ions with a positive charge
Anions- Ions with a negative charge
Define isoelectric
Having the same numbers of electrons
What is periodicity?
The repeating pattern seen by the elements in the periodic table
What is electron affinity?
The atoms ability to gain an electron and become a negative ion
What is first ionisation energy?
The energy needed for one mole of electrons to be removed from one gaseous atoms
Define ductile
Can be hammered and it doesnt break
What is oxidation?
Loss of electrons from an atom/ion
What are allotropes?
two or more differnt physical forms that an element can exist
What is redox?
The transfer of electrons during chemical reactions
