AQA A LEVEL CHEMISTRY PAPER 3
7405 3 MARK SCHEME 2026 TEST
BANK COMPLETE QUESTIONS
SOLUTIONS GRADED A+
◉ What are atoms?
Answer: Atoms are the particles that make up everything
◉ What is an element?
Answer: An element is a substance in which all the atoms are the same
◉ Where are elements shown?
Answer: Elements are shown in the Periodic table
◉ How many elements are there?
Answer: There are around 118 elements
◉ What is a compound?
Answer: A compound is a substance that contain two or more elements
chemically combined
◉ Describe the properties of compounds
Answer: The properties of compounds are usually different to the
elements that they are made from
,◉ What is a mixture?
Answer: A mixture is a substance with different elements or compounds
not chemically combined
◉ Give an example of a mixture
Answer: An example of a mixture is sand and water as they are not
chemically combined and can be separated by physical means
◉ What is a molecule?
Answer: A molecule is a substance that has any elements chemically
joined
◉ What does a chemical formula tell you about a molecule?
Answer: A chemical formula tells the elements in a molecule and the
number of atoms of each element
◉ How is a chemical formula presented?
Answer: Each element symbol starts with a capital letter, if there is a
second letter it is in lower case
◉ Give an example of a chemical formula
Answer:
,◉ What are state symbols?
Answer: State symbols show the physical state of the substance solid (s),
liquid (l), gas (g), or dissolved in water (aq)
◉ Name three properties of Metals
Answer: -Strong
-Good conductors of heat and electricity
-High melting and boiling points
◉ Name three properties of Non-Metals
Answer: -Weak
-Bad conductors of heat and electricity
-Low melting and boiling points
◉ State the four different ways of separating mixtures
Answer: Four different ways of separating mixtures are filtration,
crystallisation, distillation or chromatography
◉ Describe the process of filtration
Answer: Pour your mixture onto the filter paper, the liquid simply passes
through the filter paper into the flask. The insoluble solid cannot pass
through and so it stays on the paper
◉ Describe the process of crystallisation
, Answer: Use the method of filtration to filter off any excess soluble
solid. Evaporate the mixture then transfer the hot mixture onto a dish.
Crystals are formed when the mixture has cooled
◉ Describe the process of simple distillation
Answer: First we evaporate the mixture by heating it, the dissolved solid
then vaporises. These vapours condense in the condenser, the dissolved
solid then flows into the beaker and liquid stays in the flask
◉ Describe the process of chromatography
Answer: Take a strip of filter paper and draw a line on the bottom of the
paper. Put a small drop of ink on the line, take a jar full of water up to
the line and put the filter paper in. As the water moves up we see
different colours on the paper these are the dyes in the ink
◉ What were the early ideas of the structure of atoms?
Answer: Early ideas of the structure of atoms stated that they are tiny
spheres that cannot be divided
◉ What is the plum pudding model?
Answer: The plum pudding model is what scientists suggested is the
structure of atoms is after the discovery of the electron
◉ Describe the plum pudding model
Answer: The plum pudding model suggested that an atom is a ball of
positive charge with negative electrons in embedded in it
7405 3 MARK SCHEME 2026 TEST
BANK COMPLETE QUESTIONS
SOLUTIONS GRADED A+
◉ What are atoms?
Answer: Atoms are the particles that make up everything
◉ What is an element?
Answer: An element is a substance in which all the atoms are the same
◉ Where are elements shown?
Answer: Elements are shown in the Periodic table
◉ How many elements are there?
Answer: There are around 118 elements
◉ What is a compound?
Answer: A compound is a substance that contain two or more elements
chemically combined
◉ Describe the properties of compounds
Answer: The properties of compounds are usually different to the
elements that they are made from
,◉ What is a mixture?
Answer: A mixture is a substance with different elements or compounds
not chemically combined
◉ Give an example of a mixture
Answer: An example of a mixture is sand and water as they are not
chemically combined and can be separated by physical means
◉ What is a molecule?
Answer: A molecule is a substance that has any elements chemically
joined
◉ What does a chemical formula tell you about a molecule?
Answer: A chemical formula tells the elements in a molecule and the
number of atoms of each element
◉ How is a chemical formula presented?
Answer: Each element symbol starts with a capital letter, if there is a
second letter it is in lower case
◉ Give an example of a chemical formula
Answer:
,◉ What are state symbols?
Answer: State symbols show the physical state of the substance solid (s),
liquid (l), gas (g), or dissolved in water (aq)
◉ Name three properties of Metals
Answer: -Strong
-Good conductors of heat and electricity
-High melting and boiling points
◉ Name three properties of Non-Metals
Answer: -Weak
-Bad conductors of heat and electricity
-Low melting and boiling points
◉ State the four different ways of separating mixtures
Answer: Four different ways of separating mixtures are filtration,
crystallisation, distillation or chromatography
◉ Describe the process of filtration
Answer: Pour your mixture onto the filter paper, the liquid simply passes
through the filter paper into the flask. The insoluble solid cannot pass
through and so it stays on the paper
◉ Describe the process of crystallisation
, Answer: Use the method of filtration to filter off any excess soluble
solid. Evaporate the mixture then transfer the hot mixture onto a dish.
Crystals are formed when the mixture has cooled
◉ Describe the process of simple distillation
Answer: First we evaporate the mixture by heating it, the dissolved solid
then vaporises. These vapours condense in the condenser, the dissolved
solid then flows into the beaker and liquid stays in the flask
◉ Describe the process of chromatography
Answer: Take a strip of filter paper and draw a line on the bottom of the
paper. Put a small drop of ink on the line, take a jar full of water up to
the line and put the filter paper in. As the water moves up we see
different colours on the paper these are the dyes in the ink
◉ What were the early ideas of the structure of atoms?
Answer: Early ideas of the structure of atoms stated that they are tiny
spheres that cannot be divided
◉ What is the plum pudding model?
Answer: The plum pudding model is what scientists suggested is the
structure of atoms is after the discovery of the electron
◉ Describe the plum pudding model
Answer: The plum pudding model suggested that an atom is a ball of
positive charge with negative electrons in embedded in it
