Topic 1: Let's React Flashcards
Define Atoms
All of the materials around us are made up of tiny building block
Define Element
When a substance is made up of one type of atom
Proton: Location, Mass, Electrical Charge
nucleus, X1800, +1 charge
Electron: Location, Mass, Electrical Charge
shell around the nuclues, X1800, no charge
Neutron: Location, Mass, Electrical Charge
Shell around the nucleus, 1, -1 charge
How to find no. of neutrons?
Mass number - atomic number
Rule the maximum number of electrons each shell can hold.
2n^2, where n = the shell number
Electronic Configuration
2,8,8,2
What do the periods show on the periodic table?
The number of shells that contain electrons. It is numbered 1-7.
What do the groups show on the periodic table?
The number of electrons in the outer (valence) shell. For groups 13-18, subtract 10.
What does the atomic number of an element tell us?
The amount of electrons and protons in an element.
What does the mass number of an element tell us?
How many protons + neutrons.
What is the ground state
Electrons in the lowest energy shells
What does heating an element cause it to do?
- causes an electron to absorb energy and jump to a higher energy level.
- the electron is excited and unstable and quickly returns to a lower energy level
- releases a fixed amount of energy in the form of coloured light!!
- visible light can be emitted when electrons return to a lower energy level
What ion causes the flame colour to differ? Give evidence
It is the metal cation causing the flame colour as we tested compounds where different metal cations bonded with the same ion.
List 3 limitations of flame tests
- Different metals may produce similar flame colours
- Most metal ions are not excited by the flame of a bunsen burner as it is not hot enough
- Low accuracy and the tests are purely qualitative.
Applications of flame tests
- Fireworks
- Electric Street Signs
- Street Lights (Sodium Chloride)
What is an excited state?
any energy state higher than the ground state. It is less stable and tends to return to the ground state by releasing energy in the form of light.
What is a photon?
Coloured light energy
What is an ion?
is an atom or a group of atoms that has an electrical charge, either positive or negative