History
Ancient Greeks believed matter was made up of these elements:
Water Earth Fire Air
What are the three subatomic particles in the atom?
Protons, neutrons and electrons
What is an ion?
A charged atom
What does mass number refer to?
Number of protons + neutrons
What does the word 'atomos' mean?
Indivisible
Which subatomic particle is not located in the nucleus?
Electrons
What is the net charge when an electron is added to an atom?
Negative
What is an isotope?
Forms of the same atom with different number of neutrons
The current model of the atomic structure says electrons exist in a _______
Cloud
What is the overall charge of the nucleus?
Positive due to protons being positive and neutrons having no charge
It has lost 2 electrons
What is the main difference between carbon-12 and carbon-14?
Carbon 14 has 2 more neutrons (8) than carbon-12 (6)
This scientist suggested the plum pudding model, where the atom is a round positive ball with electrons embedded into it
J. J. Thomson
What are the relative masses of the subatomic particles?
Protons and neutrons have similar mass while electrons have about 1/2000th of the mass
A positive ion is called a/an ______
A negative ion is called a/an _______
Cation
Anion
An electrically neutral atom of lithium has an atomic number of 3 and a mass number of 7.
Identify the correct order of the number of protons, neutrons and electrons.
3 protons, 4 neutrons, 3 electrons
What did the gold foil experiment conducted by Ernest Rutherford discover?
The nucleus is positive, small and dense in the centre and most of the space surrounding it is empty, where electrons exist
Describe the arrangement of the subatomic particles that make up an atom.
An atom is made up of three types of subatomic particles.
Protons and neutrons are located in the densely packed nucleus at the centre of the atom. The nucleus is tiny compared to the size of the whole atom, which is mostly empty space.
Electrons are located in the empty space around the nucleus, randomly whizzing around
Marianne argues that the electrons in an atom should repel each other because they all have a negative charge so should fly off. Suggest a reason why electrons tend to stay in the atom.
The electrons have a like charge, so they do repel each other. However, they are attracted to the opposite (positive) charge of protons in the nucleus. This attraction causes electrons to tend to stay in the atom instead of flying off.
Why are some isotopes made purposely and give one named example with its use
They are useful in life such as in the medical field e.g. Cobalt-60 treatment or for war e.g. Uranium-235 atomic bombs