GCSE CHEMISTRY GCSE PAPER 1 EXAM REVISION QUESTIONS
WITH VERIFIED SOLUTIONS LATEST 2025 UPDATE.
What is an atom? - ANSWER- Smallest part of an element that can exist
What is an element? - ANSWER- A substance made up of one type of atom
How are elements represented? - ANSWER- Using symbols, in the periodic table
Approximately how many elements are there? - ANSWER- 100
What is a compound? - ANSWER- A substance made up of two or more elements chemically
combined in fixed proportions
How are the elements in a compound separated? - ANSWER- By chemical reaction
How are chemical reactions represented? - ANSWER- By word or symbol equations
Which group of the periodic table includes sodium and potassium? - ANSWER- Group 1, alkali
metals
Which group of the periodic table includes chlorine, bromine and iodine? - ANSWER- Group
7, halogens
Which group of the periodic table includes helium, neon and argon? - ANSWER- Group 0,
noble gases
,What information does a chemical formula provide? - ANSWER- Which elements are bonded
together, and how many atoms of each are present
What is a mixture? - ANSWER- Two or more elements or compounds not chemically bonded
together
Which separation technique is used to separate a mixture of two liquids? - ANSWER-
Distillation
Which separation technique is used to separate a mixture of more than two liquids? - ANSWER-
Fractional distillation
Which separation technique is used to separate an insoluble solid and a liquid? - ANSWER-
Filtration
Which separation technique is used to separate a mixture of coloured substances? - ANSWER-
Chromatography
Which separation technique is used to separate a soluble solid from its solution? - ANSWER-
Crystallisation
Before the discovery of the electron what were atoms thought to be? - ANSWER- Tiny spheres
that could not be divided
What is the 'plum pudding' model of the atom? - ANSWER- Ball of positive charge with
negative electrons embedded in it
What experiment led to the development of the nuclear model? - ANSWER- Rutherford's alpha
particle scattering experiment
,What happened to the alpha particles fired at thin gold foil in Rutherford's scattering experiment?
- ANSWER- Most alpha particles went straight through, but a few were scattered
What is the 'nuclear' model of the atom that Rutherford developed that replaced the 'plum pudding'
model? - ANSWER- Mass of the atom is in the centre (nucleus) and the nucleus was positively
charged
Who proposed that electrons orbit the nucleus at specific distances? - ANSWER- Niels Bohr
What name was given to the positive particles in the nucleus? - ANSWER- Protons
What did James Chadwick discover? - ANSWER- Neutrons
In what order were the subatomic particles discovered? - ANSWER- Electron, proton, neutron
What is the relative charge on a proton? - ANSWER- +1 (positive 1)
What is the relative charge on a neutron? - ANSWER- 0 (no charge)
What is the relative charge on an electron? - ANSWER- -1 (negative 1)
Why are atoms electrically neutral? - ANSWER- Number of protons = number of electrons
What name is given to the number of protons in an atom of an element? - ANSWER- Atomic
number
What does the atomic number (number of protons) determine? - ANSWER- The element.
Atoms of a particular element have the same number of protons
, What is the approximate size of an atom? - ANSWER- 0.1 nm (1 x 10-10 m)
What is the approximate radius of a nucleus? - ANSWER- 1 x 10-14 m
Where is almost all the mass of an atom? - ANSWER- In the nucleus
What is the relative mass of a proton? - ANSWER- 1
What is the relative mass of a neutron? - ANSWER- 1
What is the relative mass of an electron? - ANSWER- Very small / negligible
What name is given to the sum of the number of protons and neutrons? - ANSWER- Mass
number
What are isotopes? - ANSWER- Atoms of the same element with different numbers of neutrons
(same number of protons)
What is relative atomic mass, Mr, of an element? - ANSWER- Average mass of an element's
atoms, compared to 1/12th the mass of a carbon-12 atom
How is Mr calculated? - ANSWER- Mr = (Ar 1 x abundance 1)/100 + (Ar 2 x abundance 2)/100
What is the 'electronic structure' of an atom? - ANSWER- Shows where in the atoms the
electrons are situated
How is the electronic structure of an atom represented? - ANSWER- By numbers or a diagram
WITH VERIFIED SOLUTIONS LATEST 2025 UPDATE.
What is an atom? - ANSWER- Smallest part of an element that can exist
What is an element? - ANSWER- A substance made up of one type of atom
How are elements represented? - ANSWER- Using symbols, in the periodic table
Approximately how many elements are there? - ANSWER- 100
What is a compound? - ANSWER- A substance made up of two or more elements chemically
combined in fixed proportions
How are the elements in a compound separated? - ANSWER- By chemical reaction
How are chemical reactions represented? - ANSWER- By word or symbol equations
Which group of the periodic table includes sodium and potassium? - ANSWER- Group 1, alkali
metals
Which group of the periodic table includes chlorine, bromine and iodine? - ANSWER- Group
7, halogens
Which group of the periodic table includes helium, neon and argon? - ANSWER- Group 0,
noble gases
,What information does a chemical formula provide? - ANSWER- Which elements are bonded
together, and how many atoms of each are present
What is a mixture? - ANSWER- Two or more elements or compounds not chemically bonded
together
Which separation technique is used to separate a mixture of two liquids? - ANSWER-
Distillation
Which separation technique is used to separate a mixture of more than two liquids? - ANSWER-
Fractional distillation
Which separation technique is used to separate an insoluble solid and a liquid? - ANSWER-
Filtration
Which separation technique is used to separate a mixture of coloured substances? - ANSWER-
Chromatography
Which separation technique is used to separate a soluble solid from its solution? - ANSWER-
Crystallisation
Before the discovery of the electron what were atoms thought to be? - ANSWER- Tiny spheres
that could not be divided
What is the 'plum pudding' model of the atom? - ANSWER- Ball of positive charge with
negative electrons embedded in it
What experiment led to the development of the nuclear model? - ANSWER- Rutherford's alpha
particle scattering experiment
,What happened to the alpha particles fired at thin gold foil in Rutherford's scattering experiment?
- ANSWER- Most alpha particles went straight through, but a few were scattered
What is the 'nuclear' model of the atom that Rutherford developed that replaced the 'plum pudding'
model? - ANSWER- Mass of the atom is in the centre (nucleus) and the nucleus was positively
charged
Who proposed that electrons orbit the nucleus at specific distances? - ANSWER- Niels Bohr
What name was given to the positive particles in the nucleus? - ANSWER- Protons
What did James Chadwick discover? - ANSWER- Neutrons
In what order were the subatomic particles discovered? - ANSWER- Electron, proton, neutron
What is the relative charge on a proton? - ANSWER- +1 (positive 1)
What is the relative charge on a neutron? - ANSWER- 0 (no charge)
What is the relative charge on an electron? - ANSWER- -1 (negative 1)
Why are atoms electrically neutral? - ANSWER- Number of protons = number of electrons
What name is given to the number of protons in an atom of an element? - ANSWER- Atomic
number
What does the atomic number (number of protons) determine? - ANSWER- The element.
Atoms of a particular element have the same number of protons
, What is the approximate size of an atom? - ANSWER- 0.1 nm (1 x 10-10 m)
What is the approximate radius of a nucleus? - ANSWER- 1 x 10-14 m
Where is almost all the mass of an atom? - ANSWER- In the nucleus
What is the relative mass of a proton? - ANSWER- 1
What is the relative mass of a neutron? - ANSWER- 1
What is the relative mass of an electron? - ANSWER- Very small / negligible
What name is given to the sum of the number of protons and neutrons? - ANSWER- Mass
number
What are isotopes? - ANSWER- Atoms of the same element with different numbers of neutrons
(same number of protons)
What is relative atomic mass, Mr, of an element? - ANSWER- Average mass of an element's
atoms, compared to 1/12th the mass of a carbon-12 atom
How is Mr calculated? - ANSWER- Mr = (Ar 1 x abundance 1)/100 + (Ar 2 x abundance 2)/100
What is the 'electronic structure' of an atom? - ANSWER- Shows where in the atoms the
electrons are situated
How is the electronic structure of an atom represented? - ANSWER- By numbers or a diagram
