C1: Atomic Structure And The Periodic Table (triple) Flashcards
What is the radius of an atom?
0.1 nanometers.
Describe the process of evaporation.
- Pour solution into an evaporating dish
- Slowly heat the solution. The solvent will evaporate off.
- Keep heating the dish until only crystals are left.
Describe the process of crystallisation.
- Pour the solution into an evaporating dish and slowly heat.
- When crystals start to form, remove the dish.
- Leave the solution to cool and more crystals will form as the salt becomes insoluble in the solution.
- Filter out crystals and leave them in a worm place to dry.
How does simple distillation separate out solutions?
Part of the solution boils and evaporates. This vapour is cooled in a condenser and condenses into a separate collection area.
Describe how fractional distillation separates mixtures of liquids.
The mixture is slowly heated until one of the components evaporates. This rises and is condensed in a condenser and collected. The temperature is risen again until another component reaches its boiling point and the process repeats.
Describe the plumb pudding model.
A ball of positive charge with electrons stuck inside.
How did Rutherford prove the plumb pudding model wrong?
Alpha particles were fired at a thin piece of gold. Most passed through but some deflected more than expected and even backwards. This was explained by his nuclear model with a positive nucleus at the centre with a cloud of electrons around it.
How did Niels Bohr change the nuclear model?
He arranged the electrons in shells that orbited the nucleus.
Who discovered the proton?
Ernest Rutherford.
Who discovered the neutron?
James Chadwick.
How were elements organised in the periodic table in the early 1800s?
In order of relative atomic mass.
How did Mendeleev change the early periodic table.
He changed to order of some of the elements so their properties matched with others. He left gaps in the table to make sure elements with similar properties stayed together. His ideas were confirmed when newly discovered elements fit in these gaps.
How do alkali metals react with water?
They react vigorously producing hydrogen and a hydroxide. These dissolve in water to make an alkaline solution.
What are the trends of the halogens as you go down the group?
Become less reactive
Higher melting and boiling points
Higher relative atomic masses
What happens to the boiling point of the Nobal gasses as you go down the group?
They increase as you go down because there are more electrons in each atom so there is a greater force required to pull them apart.
What is an isotope?
an atom with a different number of neutrons.
