AS Level Chemistry 2025
1 mole - ANSThe amount of substance that contains as many elementary particles as there are in 12 of carbon
12.
1st Ionisation energy - ANSThe energy change when 1 mole of electrons is removed from 1 mole of gaseous
atoms to form 1 mole of gaseous 1+ions
Acceleration - ANSThey are accelerated through magnetic/electric field
Acid - ANSProton donor
Acid + Ammonia - ANSAcid + Ammonia 》Ammonium Salt
Acid + Base neutralisation - ANSAcid + Base 》Salt + Water
Acid + Carbonate - ANSAcid + Carbonate 》Salt + Water + Carbon Dioxide
Acid + Metal - ANSAcid + Metal 》Salt + Hydrogen (REDOX)
Activation energy - ANSThe minimum energy needed for a reaction to take place.
Addition polymerisation - ANSIdentify the monomer formed
Made by the double bond breaking in an alkene and bonding to the same alkene to form a long chain of small
molecules of monomers which is a polymer.
Alcohol - ANSA compound with an OH functional group present.
If its the only functional group then its an alcohol if there are other functional groups then its a hydroxyl group.
Aldehyde - ANSA compound with a carbonyl group attached to one hydrogen and one R group and is at the
END of the compound. (al)
,Alicyclic compounds - ANSThey are compounds that have a carbon ring unsaturated or not but does not have
aromatic character.
Aliphatic - ANSA compound containing carbon and hydrogen in straight chains branched chains or non-aromatic
rings.
Alkali - ANSSOLUBLE BASE (NaOH, KOH, NH3)
Alkane - ANSA hydrocarbon which is saturated (-ane)
Alkene - ANSA hydrocarbon which is unsaturated as it contains at least one double bond (-ene)
Amine - ANSA nitrogen attached to two hydrogen's and an R group at the end of an compound normally found
on amino acids
Ammonium ion test - ANSWarm NH4+ with NaOH producing NH3 gas which turns MOIST RED LITMUS- BLUE
Angular (bent) - ANS2=BP 2=LP A=104.5°
4 electron pairs
Anhydrous - ANSA compound with no waters of crystallisation.
Aromatic compounds - ANSThey are compounds that have delocalized pi clouds instead of discrete single and
double bonds and so the bonds can move through out the structure. (Contain a benzene ring)
Arrangement of atoms on the periodic table - ANSIncreasing atomic number
Periods showing repeating physical/chemical properties
Groups have similar chemical properties
Atomic number - ANSNumber of protons in an element
, Avogadro's constant (Number of particles per mole) - ANS6.02e^23
Avogadro's law - ANSEqual volumes of gases measured at the same temperature and pressure will contain the
same number of molecules.
Base - ANSProton acceptor.
Boltzmann distribution graph - ANSThis graph:
Goes through origin=no particles had zero energy.
There's no max energy as curve doesn't meet horizontal axis.
Area under graph=Total number of particles.
Bond enthalpy - ANSEnthalpy change required to break and seperate 1 mol of bonds in the molecules of a gas
so that the resulting gaseous particles exert no forces upon each other. They are specific to a type of bond, they
are also averages of the same bond.
Bonding in alkenes - ANSThe double bond- single covalent bond of 2 shared pair of electrons, with electron
density concentrated between nuclei. (sigma bond).
A pi bond is sideways overlap of two p-orbitals on adjacent carbon atoms providing one electron. Prevents
rotation and movement around the double bond.
The C-H bond is about 120 (trigonal planar). If there's other alkyl groups attached have bond angles of
109.5=tetrahedral.
Bonding in organic compounds - ANSCarbon- four bonds where two bond to R groups and then to other
elements. With hydrogen alkanes are symmetrical and the electronegativity difference isn't great which leads
non-polar compounds. Alcohols and halogens disturb symmetry and electronegativity so the molecules become
polar and electrons in the sigma bonds move along them to the oxygen or the halogen to stabilise molecule
(Inductive Effect).
Bromination - ANSReagent: Bromine water
Conditions: mix at RTP
Observation: Decolourisation of bromine water.
This is the test for a double bond, where it forms a dibromo product.
1 mole - ANSThe amount of substance that contains as many elementary particles as there are in 12 of carbon
12.
1st Ionisation energy - ANSThe energy change when 1 mole of electrons is removed from 1 mole of gaseous
atoms to form 1 mole of gaseous 1+ions
Acceleration - ANSThey are accelerated through magnetic/electric field
Acid - ANSProton donor
Acid + Ammonia - ANSAcid + Ammonia 》Ammonium Salt
Acid + Base neutralisation - ANSAcid + Base 》Salt + Water
Acid + Carbonate - ANSAcid + Carbonate 》Salt + Water + Carbon Dioxide
Acid + Metal - ANSAcid + Metal 》Salt + Hydrogen (REDOX)
Activation energy - ANSThe minimum energy needed for a reaction to take place.
Addition polymerisation - ANSIdentify the monomer formed
Made by the double bond breaking in an alkene and bonding to the same alkene to form a long chain of small
molecules of monomers which is a polymer.
Alcohol - ANSA compound with an OH functional group present.
If its the only functional group then its an alcohol if there are other functional groups then its a hydroxyl group.
Aldehyde - ANSA compound with a carbonyl group attached to one hydrogen and one R group and is at the
END of the compound. (al)
,Alicyclic compounds - ANSThey are compounds that have a carbon ring unsaturated or not but does not have
aromatic character.
Aliphatic - ANSA compound containing carbon and hydrogen in straight chains branched chains or non-aromatic
rings.
Alkali - ANSSOLUBLE BASE (NaOH, KOH, NH3)
Alkane - ANSA hydrocarbon which is saturated (-ane)
Alkene - ANSA hydrocarbon which is unsaturated as it contains at least one double bond (-ene)
Amine - ANSA nitrogen attached to two hydrogen's and an R group at the end of an compound normally found
on amino acids
Ammonium ion test - ANSWarm NH4+ with NaOH producing NH3 gas which turns MOIST RED LITMUS- BLUE
Angular (bent) - ANS2=BP 2=LP A=104.5°
4 electron pairs
Anhydrous - ANSA compound with no waters of crystallisation.
Aromatic compounds - ANSThey are compounds that have delocalized pi clouds instead of discrete single and
double bonds and so the bonds can move through out the structure. (Contain a benzene ring)
Arrangement of atoms on the periodic table - ANSIncreasing atomic number
Periods showing repeating physical/chemical properties
Groups have similar chemical properties
Atomic number - ANSNumber of protons in an element
, Avogadro's constant (Number of particles per mole) - ANS6.02e^23
Avogadro's law - ANSEqual volumes of gases measured at the same temperature and pressure will contain the
same number of molecules.
Base - ANSProton acceptor.
Boltzmann distribution graph - ANSThis graph:
Goes through origin=no particles had zero energy.
There's no max energy as curve doesn't meet horizontal axis.
Area under graph=Total number of particles.
Bond enthalpy - ANSEnthalpy change required to break and seperate 1 mol of bonds in the molecules of a gas
so that the resulting gaseous particles exert no forces upon each other. They are specific to a type of bond, they
are also averages of the same bond.
Bonding in alkenes - ANSThe double bond- single covalent bond of 2 shared pair of electrons, with electron
density concentrated between nuclei. (sigma bond).
A pi bond is sideways overlap of two p-orbitals on adjacent carbon atoms providing one electron. Prevents
rotation and movement around the double bond.
The C-H bond is about 120 (trigonal planar). If there's other alkyl groups attached have bond angles of
109.5=tetrahedral.
Bonding in organic compounds - ANSCarbon- four bonds where two bond to R groups and then to other
elements. With hydrogen alkanes are symmetrical and the electronegativity difference isn't great which leads
non-polar compounds. Alcohols and halogens disturb symmetry and electronegativity so the molecules become
polar and electrons in the sigma bonds move along them to the oxygen or the halogen to stabilise molecule
(Inductive Effect).
Bromination - ANSReagent: Bromine water
Conditions: mix at RTP
Observation: Decolourisation of bromine water.
This is the test for a double bond, where it forms a dibromo product.
