Atomic Structure And The Perodic Table Flashcards
What do atoms consist of?
Contain protons (positive), neutrons (no charge) and electrons (negative charge) Number of protons = number of electrons
What do elements consist?
Consist of atoms with the same atomic number. Its the number of protons in the nucleus that decides what type of atom it is.
Relative atomic equation
Sum of (isotope abundance x isotope mass number) / sum of abundance of all isotopes
What are isotopes?
Isotopes are the same as elements except for extra neutron
Explain why you shouldn’t use a pen to draw a line on the filter paper for chromatography.
Pens are soluble and can dissolve in the solvent
What is filtration?
Separates insoluble solids from liquids
Name the two ways to separate soluble solids from from solutions.
Evaporation and crystallisation
What methods can be used to separate rock salt?
Filtration - filter the sand out
Crystallisation - to evaporate the water from the salt so it forms dry crystals
Explain and describe what simple distillation is.
Simple distillation is used for separating out a liquid from a solution. Solution is heated. The part of the solution that has lowest boiling temp evaporates first. Vapour is then cooled, condenses and collected. Rest of solution left behind in flask.
What can you use simple distillation for?
To get pure water from seawater
Explain and describe what fractional distillation is.
If you’ve got a mixture of liquids you can separate it using fractional distillation.
Explain how Rutherford disproved the plum pudding model.
Because they thought positive charge of each atom was thought to be spread out through the ‘pudding’ of the atom. Whilst most of the particles did go straight through the gold sheet some deflected more than expected, small amount deflected backwards so it proved wrong
How were elements classifies in the early 1800’s
By their relative atomic mass
Their physical and chemical propertis
Describe the two changes that Mendeleev made to early periodic table.
He left gaps and predicted new elements
State the properties of metal
Strong
Good at conducting heat and electricity
They have high boiling and melting points
State properties of non - metals
Brittle
Lower density
Dull looking
Where can transition metals be found in the periodic table?
Between Groups 2 and groups 3
State the properties of transition metals
They can have more than one ion
Ions are often coloured
Make good catalysts
What are the trends for the alkali metals as you go down the group?
Increasing reactivity
Lower melting and boiling points
Higher relative atomic mass
Alkali metal + water =
Metal hydroxide + hydrogen gas
Alkali + chlorine =
Metal chloride
What is the trend as you go down group 7?
Becomes less reactive
Higher melting and boiling points
Higher relative atomic mass
Predict whether bromine would displace iodine from sodium iodide and explain why.
It would displace as it its more reactive and more reactive halogens will displace less reactive ones.
What are group 0 elements called?
Noble gasses
