What are the 3 subatomic particles? What is the mass and charge of them?
Proton
Mass: 1
Charge: +1
Neutron
Mass: 1
Charge: 0
Electron
Mass: 0
Charge: -1
What does the atomic number tell you?
The amount of protons in an element.
What does the mass number tell you?
The amount of protons and neutrons in an element.
What is the difference between an atom and an ion?
An atom has the same amount of protons and electrons whereas an ion has a different amount amount of protons and electrons.
What is a compound?
A solution of one or more elements that are chemically bonded.
What is an isotope?
A substance with different amounts of protons and neutrons.
What is a compound and how is it split up?
A compound is a solution of two or more types of elements that are chemically bonded. A compound is split up in a chemical reaction.
What is a mixture and how is it split up?
A mixture is a solution of two or more types of elements or compounds that are not chemically bonded. A mixture is split up using a physical method.
What is the difference between evaporation and crystallisation?
In evaporation, you evaporate the solvent fully to form crystals
In crystallisation, you evaporate the solution until crystals start to form and then leave the solution to cool and then filter to get crystals.
When it is appropriate to use crystallisation or evaporation?
You use evaporation when the salt that you are trying to separate does NOT decompose when heated
You use crystallisation when the salt that you are trying to separate DOES decompose when heated
When is it appropriate to use distillation or fractional distillation?
Distillation: when you want to separate liquids with very different boiling points
Fractional distillation: when you want to separate liquids with very similar boiling points
Who discovered the plum pudding model? When was it discovered?
J J Thomson in 1897
What is the plum pudding model?
A positively charge ball with negatively charged electrons scattered on it.
Who discovered the first nuclear model/Rutherford nuclear model? When was it discovered?
Ernest Rutherford in 1909
What was the first/Rutherford’s nuclear model?
A positively charged nucleus with a cloud of negatively charged electrons around it.
Who discovered the second nuclear model/Bohr’s nuclear model?
Bohr
What was the second/Bohr’s nuclear model?
A positively charged nucleus with shells of electrons orbiting the nucleus at fixed distances. No neutrons as they had not been discovered yet.
Who discovered neutrons?
James Chadwick
How was the periodic table ordered in the early 1800s?
Ordered by atomic weight
How did Mendeleev change how the periodic table was ordered?
Left gaps for elements that had not been discovered
Moved elements that had similar properties close together
How is the modern periodic table ordered?
In order of atomic number.
What are three characteristics of transition metals?
Can have multiple ions
Colourful
Useful catalysts
How do alkali/group 1 metals change as you go down the periodic table?
Become more reactive
Higher relative atomic mass
Lower melting and boiling points
How do halogens/group 7 non-metals change as you go down the periodic table?
Reactivity decreases
Melting and boiling point increases
Relative atomic mass increases
Why are group 0/noble gases unreactive?
They have a full outer shell so they do not need to share, lose or gain an electron.
What happens with the boiling point of group 0/noble gases as you go down the periodic table?
Boiling point increases.