Edexcel Combined Chemistry Paper 1:
**NOT A SUMMARY, THIS IS IN COMPLETE DETAIL**
I attained 99 in Combined Science solely through this self made resource of mine. I have
painstakingly gathered information from every EDEXCEL specific resource I could lay my hands on
(including seneca, pmt, savemyexams, lit every single video on each topic i could find and the
EDEXCEL textbook itself) in order to create this incredibly precise document. It meets every single
specification point in meticulous detail, including diagrams and lengthy explanations where needed. It
is the boiling pot of absolutely every single thing you need to know, nothing more n nothing less, to
seize your 99 in GCSE Combined Science.
Key:
- Boldened sentence: Specification point itself
Topic 0:
,Topic 1: ATOMIC STRUCTURE (Key concepts, this is in both Paper 1 and
Paper 2)
1.1 Describe how the Dalton model of an atom has changed over time because of the
discovery of subatomic particles
John Dalton (1803):
He published his own three-part atomic theory:
● All substances are made of atoms. Atoms are small particles that cannot be
created, divided or destroyed.
● Atoms of the same element are exactly alike, and atoms of different elements are
different.
, ● Atoms join with other atoms to make new substances.
J.J Thompson:
Used cathode-ray tube experiment proving that atoms can be divided into smaller parts as
the beam moved away from the negative charged plate to the positive charged plate,
meaning that atoms had a negative charge present. So he modelled the ‘plum pudding
model’ An atom being a sea of positive mass with ‘plums’ of electron scattered throughout.
Ernest Rutherford: He shot beams of positively charged atoms at a thin sheet of gold foil.
Most atoms continued in a straight line but some deflected and few even completely
bounced back suggesting that the mass of the atom is concentrated at the centre known as
the nucleus, the rest being empty space with electrons travelling in random paths around the
nucleus.
Neils Bohr: Found that electrons orbit the nucleus at fixed distances. This model solved the
question of why the atom did not collapse inwards due to the attraction between the positive
nucleus and negative electrons circling the nucleus.
, James Chadwick: His idea was based on the differences between atomic mass and atomic
number of atoms, where he found neutral particles within the nucleus.
As a result of these discoveries, we now know that:
● atoms can be broken down into three smaller particles: protons, neutrons and
electrons
● atoms of an element have identical numbers of protons and electrons, but can
have different numbers of neutrons
● atoms of different elements have different numbers of protons and electrons
1.2 Describe the structure of an atom as a nucleus containing protons and neutrons,
surrounded by electron shells
1.3 Recall the relative charge and relative mass of protons, neutrons and electrons
1.4 Explain why atoms contain equal numbers of protons and electrons
Atoms are neutral and charges on a proton and electron are -1 so therefore the protons =
electrons so charges can cancel to create an atom, not an ion.
1.5 Describe the nucleus of an atom as very small compared to the overall size of the
atom
1.6 Recall that most of the mass of an atom is concentrated in the nucleus (Both spec
addressed at once)
Atoms have the radius of about 1 x 10^-10 metres. The radius of the nucleus is 1 × 10 ^-14
m, which is 10,000 times smaller than the atom, so it is an extremely small region of space
compared to the overall size of the atom.
This means that the atom’s matter is not evenly spread out, but instead concentrated inside
the nucleus.
1.7 Recall the meaning of the term mass number of an atom
Mass number = protons + neutrons
1.8 Describe atoms of a given element as having the same number of protons in the
nucleus and that this number is unique to that element
Proton number never changes. If it does, it means you have an entirely different element.
Proton numbers are therefore unique to each element.
1.9 Describe isotopes as different atoms of the same element containing the same
number of protons but different numbers of neutrons in their nuclei
Isotopes are atoms of the same element that contain the same number of protons and
electrons, but a different number of neutrons. Isotopes display the same chemical
**NOT A SUMMARY, THIS IS IN COMPLETE DETAIL**
I attained 99 in Combined Science solely through this self made resource of mine. I have
painstakingly gathered information from every EDEXCEL specific resource I could lay my hands on
(including seneca, pmt, savemyexams, lit every single video on each topic i could find and the
EDEXCEL textbook itself) in order to create this incredibly precise document. It meets every single
specification point in meticulous detail, including diagrams and lengthy explanations where needed. It
is the boiling pot of absolutely every single thing you need to know, nothing more n nothing less, to
seize your 99 in GCSE Combined Science.
Key:
- Boldened sentence: Specification point itself
Topic 0:
,Topic 1: ATOMIC STRUCTURE (Key concepts, this is in both Paper 1 and
Paper 2)
1.1 Describe how the Dalton model of an atom has changed over time because of the
discovery of subatomic particles
John Dalton (1803):
He published his own three-part atomic theory:
● All substances are made of atoms. Atoms are small particles that cannot be
created, divided or destroyed.
● Atoms of the same element are exactly alike, and atoms of different elements are
different.
, ● Atoms join with other atoms to make new substances.
J.J Thompson:
Used cathode-ray tube experiment proving that atoms can be divided into smaller parts as
the beam moved away from the negative charged plate to the positive charged plate,
meaning that atoms had a negative charge present. So he modelled the ‘plum pudding
model’ An atom being a sea of positive mass with ‘plums’ of electron scattered throughout.
Ernest Rutherford: He shot beams of positively charged atoms at a thin sheet of gold foil.
Most atoms continued in a straight line but some deflected and few even completely
bounced back suggesting that the mass of the atom is concentrated at the centre known as
the nucleus, the rest being empty space with electrons travelling in random paths around the
nucleus.
Neils Bohr: Found that electrons orbit the nucleus at fixed distances. This model solved the
question of why the atom did not collapse inwards due to the attraction between the positive
nucleus and negative electrons circling the nucleus.
, James Chadwick: His idea was based on the differences between atomic mass and atomic
number of atoms, where he found neutral particles within the nucleus.
As a result of these discoveries, we now know that:
● atoms can be broken down into three smaller particles: protons, neutrons and
electrons
● atoms of an element have identical numbers of protons and electrons, but can
have different numbers of neutrons
● atoms of different elements have different numbers of protons and electrons
1.2 Describe the structure of an atom as a nucleus containing protons and neutrons,
surrounded by electron shells
1.3 Recall the relative charge and relative mass of protons, neutrons and electrons
1.4 Explain why atoms contain equal numbers of protons and electrons
Atoms are neutral and charges on a proton and electron are -1 so therefore the protons =
electrons so charges can cancel to create an atom, not an ion.
1.5 Describe the nucleus of an atom as very small compared to the overall size of the
atom
1.6 Recall that most of the mass of an atom is concentrated in the nucleus (Both spec
addressed at once)
Atoms have the radius of about 1 x 10^-10 metres. The radius of the nucleus is 1 × 10 ^-14
m, which is 10,000 times smaller than the atom, so it is an extremely small region of space
compared to the overall size of the atom.
This means that the atom’s matter is not evenly spread out, but instead concentrated inside
the nucleus.
1.7 Recall the meaning of the term mass number of an atom
Mass number = protons + neutrons
1.8 Describe atoms of a given element as having the same number of protons in the
nucleus and that this number is unique to that element
Proton number never changes. If it does, it means you have an entirely different element.
Proton numbers are therefore unique to each element.
1.9 Describe isotopes as different atoms of the same element containing the same
number of protons but different numbers of neutrons in their nuclei
Isotopes are atoms of the same element that contain the same number of protons and
electrons, but a different number of neutrons. Isotopes display the same chemical
