The periodic table Flashcards
Define first ionisation energy:
(The energy required to) remove one mole of electrons from one mole of gaseous
atoms.
List factors affecting first ionisation energy:
The strength of attraction between
the electron and the nucleus, the nuclear charge and the atomic radius. There is a small decrease in first ionisation energy due to s- and p-subshell energies (between Be and B) and p-orbital repulsion (between N and O).
What is a giant covalent lattice?
A network of atoms bonded by strong covalent bonds (e.g. carbon
(diamond, graphite and graphene) and silicon). Giant covalent lattices typically insoluble with a high melting and boiling point due to the presence of strong covalent bonds. They are also
poor electrical conductors as they don’t contain mobile charged particles.
What is a Giant Metallic Lattice Structure
The structure of all metals, made up of cations and
delocalised electrons. Giant metallic structures are typically insoluble with a high melting and boiling points due to strong electrostatic forces of attraction between cations and electrons. Metals are good electrical conductors due to the presence of delocalised electrons (mobile
charges).
What is Metallic Bonding?
Bonding caused by strong electrostatic attraction between cations and delocalised electrons.
What is periodicity?
A repeating trend in physical and chemical properties across the periods of the periodic table.
Define Successive Ionisation Energies
The energy required to remove each electron one-by-one
from one mole of gaseous atoms / ions.
What is a Bronsted- Lowry base?
A substance that can accept H+ ions from another substance.
What is a Bronsted- Lowry acid?
A substance that can donate H+ ions to another substance.
What is a displacement reaction?
A reaction in which one atom is replaced by another.
Describe the trend in displacement reactions of halogens:
Halogens can
undergo displacement reactions as their reactivity decreases down the group. The more reactive halogen will displace the less reactive halogen from a solution of its salt.
What is disproportionation? List examples.
the oxidation and reduction of the same element. Examples include the water treatment (reacting chlorine with water) and bleach formation (reacting chlorine with cold, dilute aqueous sodium hydroxide).
What are Induced Dipole-Dipole Interactions/ London forces?
Forces of attraction between molecules caused when
the random movement of electrons creates a temporary dipole in one molecule which then induces a dipole in a neighbouring molecule.
Describe risks associated with chlorine in water treatment.
The risks associated with the use of chlorine to treat water are the hazards of toxic chlorine gas and the possible risks
from the formation of chlorinated hydrocarbons
State the equation for use of chlorine in water treatment.
Cl2(g) + H2O(l) ⇌ HCl(aq) + HClO(aq)
