A LEVEL CHEMISTRY A: PERIODIC TABLE,
ELEMENTS AND PHYSICAL CHEMISTRY
CERTIFICATION SCRIPT 2026 QUESTIONS
WITH SOLUTIONS GRADED A+
◍ Democritus.
Answer: Among the first to suggest the existence of atoms. Believed that
atoms were indivisible and indestructible
◍ John Dalton.
Answer: Used the scientific method to prove Democritus' ideas and created
Dalton's atomic theory
◍ JJ Thomson.
Answer: Discovered the electron using the cathode ray. Plum pudding model
◍ Robert Millikan.
Answer: Discovered the quantity of charge carried by the electron, and the
mass of the electron
◍ Eugen Goldstein.
Answer: Used the cathode ray tube to discover the existence of protons
◍ James Chadwick.
Answer: Confirmed the existence of the neutron
◍ Explain the term atomic number.
Answer: The number of protons in the nucleus of an atom.
◍ Ernest Rutherford.
Answer: Used the gold foil experiment to conclude that atoms are mostly
empty space as well as discovering the nucleus
,◍ Louis de Broglie.
Answer: Proposed that electrons have some properties of waves
◍ Niels Bohr.
Answer: Proposed that electrons move in orbits around the nucleus and have
a fixed energy which prevents them from falling into the nucleus
◍ Explain the term mass number.
Answer: The number of protons+ neutrons in the nucleus of an atom
◍ Explain the term isotopes.
Answer: Atoms the same element with different numbers of neutrons and
different masses
◍ Erwin Schrodinger.
Answer: Created an equation that treated electrons as atoms in waves. Laid
the foundation for modern atomic theory
◍ Werner Heisenberg.
Answer: Proposed that any attempt to locate a specific electron with a
photon knocks the electron off its course
◍ J.
W. Dobereiner.
Answer: Classified elements into triads
◍ Dimitri Mendeleev.
Answer: Organized the elements based on increasing atomic mass. Gaps in
his periodic table represented undiscovered elements
◍ Henry Moseley.
Answer: Gave each element an atomic number
◍ What is chemistry?.
Answer: The study of the composition structure & properties of matter, the
processes that matter undergoes and the energy changes that accompany
these processes
, ◍ Explain the term relative isotopic mass.
Answer: The mass of an atom of an isotope compared with 1/12th of the
mass of one atom of carbon-12
◍ What 2 things must matter have?.
Answer: Mass & takes up space/volume
◍ Organic chemistry (def.).
Answer: Study of chemicals containing carbon
◍ Inorganic chemistry (def.).
Answer: Study of chemicals not containing carbon
◍ Biochemistry (def).
Answer: study of substances & processes that take place in organisms
◍ Analytical chemistry (def).
Answer: study of the composition of matter
◍ Explain the term relative atomic mass..
Answer: The weighted mean mass of an atom of an element compared to
1/12th of the mass of one atom of carbon-12
◍ Physical chemistry (def).
Answer: deals with the mechanism, rate & energy transfer of energy when
matter undergoes a change
◍ Theoretical chemistry (def).
Answer: use of math & computers to understand and predict chemical
behavior
◍ What is an atom?.
Answer: smallest unit of an element that maintains the chemical identity of
that element
◍ What is an element?.
Answer: The simplest form of matter that has a unique set of properties
◍ What is a compound?.
ELEMENTS AND PHYSICAL CHEMISTRY
CERTIFICATION SCRIPT 2026 QUESTIONS
WITH SOLUTIONS GRADED A+
◍ Democritus.
Answer: Among the first to suggest the existence of atoms. Believed that
atoms were indivisible and indestructible
◍ John Dalton.
Answer: Used the scientific method to prove Democritus' ideas and created
Dalton's atomic theory
◍ JJ Thomson.
Answer: Discovered the electron using the cathode ray. Plum pudding model
◍ Robert Millikan.
Answer: Discovered the quantity of charge carried by the electron, and the
mass of the electron
◍ Eugen Goldstein.
Answer: Used the cathode ray tube to discover the existence of protons
◍ James Chadwick.
Answer: Confirmed the existence of the neutron
◍ Explain the term atomic number.
Answer: The number of protons in the nucleus of an atom.
◍ Ernest Rutherford.
Answer: Used the gold foil experiment to conclude that atoms are mostly
empty space as well as discovering the nucleus
,◍ Louis de Broglie.
Answer: Proposed that electrons have some properties of waves
◍ Niels Bohr.
Answer: Proposed that electrons move in orbits around the nucleus and have
a fixed energy which prevents them from falling into the nucleus
◍ Explain the term mass number.
Answer: The number of protons+ neutrons in the nucleus of an atom
◍ Explain the term isotopes.
Answer: Atoms the same element with different numbers of neutrons and
different masses
◍ Erwin Schrodinger.
Answer: Created an equation that treated electrons as atoms in waves. Laid
the foundation for modern atomic theory
◍ Werner Heisenberg.
Answer: Proposed that any attempt to locate a specific electron with a
photon knocks the electron off its course
◍ J.
W. Dobereiner.
Answer: Classified elements into triads
◍ Dimitri Mendeleev.
Answer: Organized the elements based on increasing atomic mass. Gaps in
his periodic table represented undiscovered elements
◍ Henry Moseley.
Answer: Gave each element an atomic number
◍ What is chemistry?.
Answer: The study of the composition structure & properties of matter, the
processes that matter undergoes and the energy changes that accompany
these processes
, ◍ Explain the term relative isotopic mass.
Answer: The mass of an atom of an isotope compared with 1/12th of the
mass of one atom of carbon-12
◍ What 2 things must matter have?.
Answer: Mass & takes up space/volume
◍ Organic chemistry (def.).
Answer: Study of chemicals containing carbon
◍ Inorganic chemistry (def.).
Answer: Study of chemicals not containing carbon
◍ Biochemistry (def).
Answer: study of substances & processes that take place in organisms
◍ Analytical chemistry (def).
Answer: study of the composition of matter
◍ Explain the term relative atomic mass..
Answer: The weighted mean mass of an atom of an element compared to
1/12th of the mass of one atom of carbon-12
◍ Physical chemistry (def).
Answer: deals with the mechanism, rate & energy transfer of energy when
matter undergoes a change
◍ Theoretical chemistry (def).
Answer: use of math & computers to understand and predict chemical
behavior
◍ What is an atom?.
Answer: smallest unit of an element that maintains the chemical identity of
that element
◍ What is an element?.
Answer: The simplest form of matter that has a unique set of properties
◍ What is a compound?.
