AS LEVEL CHEMISTRY A Latest Update
Questions with Perfect Answers
Guaranteed Pass 100%
1 mole - Answer -The amount of substance that contains as many elementary particles as there
are in 12 of carbon 12.
1st Ionisation energy - Answer -The energy change when 1 mole of electrons is removed from 1
mole of gaseous atoms to form 1 mole of gaseous 1+ions
Acceleration - Answer -They are accelerated through magnetic/electric field
Acid - Answer -Proton donor
Acid + Ammonia - Answer -Acid + Ammonia 》Ammonium Salt
Acid + Base neutralisation - Answer -Acid + Base 》Salt + Water
Acid + Carbonate - Answer -Acid + Carbonate 》Salt + Water + Carbon Dioxide
Acid + Metal - Answer -Acid + Metal 》Salt + Hydrogen (REDOX)
Activation energy - Answer -The minimum energy needed for a reaction to take place.
Addition polymerisation - Answer -Identify 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 - Answer -A 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 - Answer -A compound with a carbonyl group attached to one hydrogen and one R group
and is at the END of the compound. (al)
Alicyclic compounds - Answer -They are compounds that have a carbon ring unsaturated or not
but does not have aromatic character.
Aliphatic - Answer -A compound containing carbon and hydrogen in straight chains branched
chains or non-aromatic rings.
Alkali - Answer -SOLUBLE BASE (NaOH, KOH, NH3)
Alkane - Answer -A hydrocarbon which is saturated (-ane)
,Alkene - Answer -A hydrocarbon which is unsaturated as it contains at least one double bond (-
ene)
Amine - Answer -A nitrogen attached to two hydrogen's and an R group at the end of an
compound normally found on amino acids
Ammonium ion test - Answer -Warm NH4+ with NaOH producing NH3 gas which turns MOIST RED
LITMUS- BLUE
Angular (bent) - Answer -2=BP 2=LP A=104.5°
4 electron pairs
Anhydrous - Answer -A compound with no waters of crystallisation.
Aromatic compounds - Answer -They 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 - Answer -Increasing atomic number
Periods showing repeating physical/chemical properties
Groups have similar chemical properties
Atomic number - Answer -Number of protons in an element
Avogadro's constant (Number of particles per mole) - Answer -6.02e^23
Avogadro's law - Answer -Equal volumes of gases measured at the same temperature and pressure
will contain the same number of molecules.
Base - Answer -Proton acceptor.
Boltzmann distribution graph - Answer -This 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 - Answer -Enthalpy 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 - Answer -The 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 - Answer -Carbon- 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 - Answer -Reagent: 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.
Cahn, Ingold and Prelog rules (CIP) - Answer -They help name the isomers as E/Z. Consider atomic
number to determine isomer shape.
1) HIGHEST Ar> DIAGONALLY OPPOSITE= E-ISOMER.
2) HIGHEST Ar> ARE NOT diagonally opposite= Z-ISOMER.
3) Same Ar then ADJACENT ATOMS considered. Alkyl groups follow
CH3CH2CH2(43)>CH3CH2(29)>CH3(15)
Calculating molecular formula - Answer -Calculate empirical formula
Use empirical formula and relative molecular mass to deduce molecular formula.
Carbonate ion test - Answer -CO3 (2-)+DILUTE ACID= Salt+Water+CO2. Effervescence of CO2 gas
proves carbonate present
Carboxylic acid - Answer -A carbonyl group attached to a hydroxyl group and an R group and is
ALWAYS AT THE END of the compound. (-oic acid)
CFCs - Answer -Haloalkanes WERE used to produce (CFCs). Used as refrigeration units, air
conditioners and in aerosols. Needed a liquid with suitable volatility, readily evaporated and re-
condensed but un-reactive, non-toxic and non-flammable. Banned by the MONTREAL PROTOCOL 1987.
HCFCs were made as they were less stable and but still formed chlorine radicals. Development on HFCs
but the nature of products is unknown and could have other harmful effects.
Chain isomerism - Answer -Have varying chain lengths like but-1-ene and methyl propene.
Chemical properties of alkanes - Answer -They are very unreactive as the C-H bond has low
polarity and the bonds are relatively strong.
Chemical properties of alkenes - Answer -Due to double bond can only take part in ADDITIONAL
reactions. Weakness of pi bond has low bond enthalpy so breaks forming extra bond for each carbon.
Questions with Perfect Answers
Guaranteed Pass 100%
1 mole - Answer -The amount of substance that contains as many elementary particles as there
are in 12 of carbon 12.
1st Ionisation energy - Answer -The energy change when 1 mole of electrons is removed from 1
mole of gaseous atoms to form 1 mole of gaseous 1+ions
Acceleration - Answer -They are accelerated through magnetic/electric field
Acid - Answer -Proton donor
Acid + Ammonia - Answer -Acid + Ammonia 》Ammonium Salt
Acid + Base neutralisation - Answer -Acid + Base 》Salt + Water
Acid + Carbonate - Answer -Acid + Carbonate 》Salt + Water + Carbon Dioxide
Acid + Metal - Answer -Acid + Metal 》Salt + Hydrogen (REDOX)
Activation energy - Answer -The minimum energy needed for a reaction to take place.
Addition polymerisation - Answer -Identify 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 - Answer -A 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 - Answer -A compound with a carbonyl group attached to one hydrogen and one R group
and is at the END of the compound. (al)
Alicyclic compounds - Answer -They are compounds that have a carbon ring unsaturated or not
but does not have aromatic character.
Aliphatic - Answer -A compound containing carbon and hydrogen in straight chains branched
chains or non-aromatic rings.
Alkali - Answer -SOLUBLE BASE (NaOH, KOH, NH3)
Alkane - Answer -A hydrocarbon which is saturated (-ane)
,Alkene - Answer -A hydrocarbon which is unsaturated as it contains at least one double bond (-
ene)
Amine - Answer -A nitrogen attached to two hydrogen's and an R group at the end of an
compound normally found on amino acids
Ammonium ion test - Answer -Warm NH4+ with NaOH producing NH3 gas which turns MOIST RED
LITMUS- BLUE
Angular (bent) - Answer -2=BP 2=LP A=104.5°
4 electron pairs
Anhydrous - Answer -A compound with no waters of crystallisation.
Aromatic compounds - Answer -They 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 - Answer -Increasing atomic number
Periods showing repeating physical/chemical properties
Groups have similar chemical properties
Atomic number - Answer -Number of protons in an element
Avogadro's constant (Number of particles per mole) - Answer -6.02e^23
Avogadro's law - Answer -Equal volumes of gases measured at the same temperature and pressure
will contain the same number of molecules.
Base - Answer -Proton acceptor.
Boltzmann distribution graph - Answer -This 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 - Answer -Enthalpy 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 - Answer -The 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 - Answer -Carbon- 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 - Answer -Reagent: 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.
Cahn, Ingold and Prelog rules (CIP) - Answer -They help name the isomers as E/Z. Consider atomic
number to determine isomer shape.
1) HIGHEST Ar> DIAGONALLY OPPOSITE= E-ISOMER.
2) HIGHEST Ar> ARE NOT diagonally opposite= Z-ISOMER.
3) Same Ar then ADJACENT ATOMS considered. Alkyl groups follow
CH3CH2CH2(43)>CH3CH2(29)>CH3(15)
Calculating molecular formula - Answer -Calculate empirical formula
Use empirical formula and relative molecular mass to deduce molecular formula.
Carbonate ion test - Answer -CO3 (2-)+DILUTE ACID= Salt+Water+CO2. Effervescence of CO2 gas
proves carbonate present
Carboxylic acid - Answer -A carbonyl group attached to a hydroxyl group and an R group and is
ALWAYS AT THE END of the compound. (-oic acid)
CFCs - Answer -Haloalkanes WERE used to produce (CFCs). Used as refrigeration units, air
conditioners and in aerosols. Needed a liquid with suitable volatility, readily evaporated and re-
condensed but un-reactive, non-toxic and non-flammable. Banned by the MONTREAL PROTOCOL 1987.
HCFCs were made as they were less stable and but still formed chlorine radicals. Development on HFCs
but the nature of products is unknown and could have other harmful effects.
Chain isomerism - Answer -Have varying chain lengths like but-1-ene and methyl propene.
Chemical properties of alkanes - Answer -They are very unreactive as the C-H bond has low
polarity and the bonds are relatively strong.
Chemical properties of alkenes - Answer -Due to double bond can only take part in ADDITIONAL
reactions. Weakness of pi bond has low bond enthalpy so breaks forming extra bond for each carbon.
