The Nucleus Flashcards
Give an approximation for the radius of an atom.
1x10^-10 metres
What are the three subatomic constituents of an atom?
- Proton
- Neutron
- Electron
Where is the most of the mass of an atom concentrated?
In the nucleus
Approximately what proportion of the total radius of an atom is the radius of the nucleus?
1/10,000
Describe the arrangement of protons, neutrons and electrons in an atom.
- Protons and neutrons are found in the atoms nucleus
- Electrons are found in discrete energy levels around the nucleus
What type of charge does the nucleus of an atom have? Why?
- Positive charge
- The nucleus contains protons and neutrons
- Protons have a positive charge
- Neutrons have no charge
Give two ways that an atom’s electron arrangement can be changed.
- Absorbing electromagnetic radiation
- Emitting electromagnetic radiation
Explain how an atom’s electron arrangement changes when it absorbs EM radiation.
- Electrons move to higher energy levels
- They move away from the nucleus
Explain how an atom’s electron arrangement changes when it emits EM radiation.
- Electrons move to a lower energy level
- They move towards the nucleus
How does the ratio of electrons to protons in an atom result in the atom having no overall charge?
- The number of protons is equal to the number of electrons
- Protons and electrons have equal and opposite charges, so charge cancels
What do all forms of the same element have in common?
The number of protons
What is the name given to the number of protons in an atom?
Atomic number
What is an atom’s number?
The total number of protons and neutrons in the atom
What is an isotope of an atom?
An atom of an element that has a different number of neutrons, but the same number of protons
What property differs between isotope of an element?
The mass of the atom
