A106 Organic and Inorganic chemistry Flashcards
What are group I elements called
Alkali metals
What are group II elements called
Alkali earth metals
What are group III to group XII elements called?
Transition metals
What are group 17 elements called?
Halogens
What are group 18 elements called?
Nobel gas
What is 1st ionisation?
It is the energy required to remove one electron from a neutron atom in its gaseous state to form a positively charged ion (Cation)
What is electronegativity?
It is the ability to form an atom to attract electrons to itself in a chemical bond
What is standard electrode potential?
It is a measure of the tendency of an electrode to gain electrons and undergo reduction
What does positive electrode potential mean?
Elements with positive electrode potential tend to gain electrons and be reduced.
It is more easily oxidised and acts as an oxidising agent
What does a negative electrode potential mean?
Elements with negative electrode potential tend to gain electrons and be oxidised.
It is more easily reduced and acts as a reducing agent
What is the trend for atomic radius across the period? and why?
Decrease
Because: Radius size increase
more proton, more attraction
What is the trend for ionic radius across the period? and why?
Decrease
Because: When atom loses electron to form cation, it is more strongly attracted, forming smaller atoms
When atom gains electron to form anion, electron repels other electrons (outer most shall), forming larger atom
What is the trend for atomic radius down the group? and why?
Increase
because: More electron, bigger radius (more filled outer most shall), thus radius increase
What is the trend of 1st ionisation across a period? and why?
Increase
Because: Number of protons in the nucleus increase, stronger nuclear charge
What is the trend for ionic radius down the group? and why?
Increase
Because: More electron, bigger the radius (more filled outer most shall), thus radius increase
What is the trend of electronegativity across a period? and why?
Increase
Because: Greater nuclear charge, smaller covalent radius (like atomic radius), allowing the nucleus to attract the bonding electrons more strongly
What is the trend of 1st ionisation down the group? and why?
Decrease
Because: Outer most electron lies further from the nucles, which experiences more repulsion, weaker attraction to the nucleus, lesser energy required to remove them.
More shielding effects
What is the trend of electronegativity down a group? and why?
Decrease
because: Atom increase in size, greater number of energy levels / shells
Extra energy levels and increased radius keeps bonding of electron further away from nucleus
Atom further down the group have lesser attraction for binding electrons
What is the value that the standard electrode potential must be lower than, in order for the element to be highly reactive with cold water?
-2.37V
What is charge density?
it is the distribution of electric charge within a molecule or ion
What does a low charge density mean?
Strong polarising power, splits carbonate into CO2 and O2-
What does low charge density means?
Weak polarising power, more thermally stable
What are the characteristics of Mg(OH2)?
Insoluble in water
White precipitate
What are the characteristics of Ca(OH)2
Reasonably soluble in water
Cloudy or milky due to part of undissolved particles
What are the physical properties of group 2 elements
- Soft silver metals, but harder than group I metals
- hydroxides are soluble down the group (except for MgOH2 and CaOH2
- Carbonates are more thermally stable down the group
What are the chemical properties of group 2 elements
- reactivity increases down the group
- Reducing agent properties increases down the group
