Starter quiz
- Which statement is true about elements?
- They are composed of multiple types of atoms.
- They can be broken down into simpler substances by chemical means.
- They are the simplest form of matter that can exist under normal conditions. ✓
- They are all metals.
-
- What determines the identity of an element?
- The number of molecules it has
- The type of atoms it is made up of ✓
- Its physical state
- Its colour
-
- In a chemical reaction, atoms...
- change into different elements.
- are destroyed.
- are created.
- rearrange to form new substances. ✓
-
- An element is a substance made up of only one kind of ...
- 'atom' ✓
- John Dalton's theory proposed that ______ are indivisible.
- 'atoms' ✓
- The ______ is a list of all known elements, ordered based on their properties.
- 'periodic table' ✓
Exit quiz
- Where is the nucleus located in an atom?
- Outside the electron shells
- In the centre ✓
- In the electron
- It varies
-
- Match the subatomic particles with their relative charges:
- electron⇔-1 ✓
- proton⇔+1 ✓
- neutron⇔0 ✓
- The relative mass of a neutron is ______ (compared to protons).
- '1' ✓
- True or false? Atoms are overall neutral. (Select true or false and a justification.)
- True ✓
- False
- they have the same numbers of protons and neutrons
- they have the same numbers of protons and electrons ✓
- they have the same numbers of electrons and neutrons
-
- Which of the following are correct ways of describing the relative mass of electrons (compared to protons)?
- 0.0005 ✓
- 1/2000 ✓
- 0
- -1
- 0.1835
-
- The radius of an atom's ______ is at least 10 000 times smaller in comparison to the radius of the whole atom.
- 'nucleus' ✓
Worksheet
Presentation
Video
Lesson Details
Key learning points
- Electrons have a relative charge of -1 and roughly a relative mass of 0.0005.
- Protons are found in the atomic nucleus, have a relative electric charge of +1, and a relative mass of 1.
- Neutrons are found in the atomic nucleus, have no electric charge, and a relative mass of 1.
- An atom has no electric charge and contains equal numbers of protons and electrons to balance the charge.
- The atom has a nucleus surrounded by electrons, with the nuclear radius much smaller than that of the atom.
Common misconception
Students often struggle with the idea of how small an atom actually is. In contrast, how small the nucleus is, relative to the size of the atom.
The use of units and numbers to show the difference in size, e.g. the atom is approximately 10, 000 times larger than the nucleus. The radius of the nucleus is 0.00001nm, compared to that of the atom which is 0.1nm.
Keywords
Electron - An electron is a subatomic particle with a negative charge and a very small relative atomic mass of 0.0005.
Proton - A proton is a subatomic particle with a positive charge and a relative atomic mass of 1.
Neutron - A neutron is a subatomic particle with no charge and a relative atomic mass of 1.
Nucleus - A nucleus is found in the centre of an atom. It consists of protons and neutrons. It is significantly smaller in size than the atom.
Subatomic - Anything that is smaller than an atom. There are three subatomic particles called electrons, protons and neutrons.