4.1.1 Atomic structure (might need to know) PAPER 1 Flashcards
What are compounds
Substances formed from 2 or more elements chemically combined in fixed proportions
What is a mixture
A mixture consists of two or more elements or compounds not chemically combined together
How can mixtures be separated with examples
Physical processes Filtration Crystallisation Simple distillation Fractional distillation Chromatography
What did the plum pudding model suggest
The plum pudding model suggested that the atom is a ball of positive charge with negative electrons embedded in it
How was the nuclear model created and what did it suggest
The results from the alpha particle scattering experiment led to the conclusion that the mass of an atom was concentrated at the centre (nucleus) and that the nucleus was charged
How did Niels Bohr adapt the nuclear model
Niels Bohr adapted the nuclear model by suggesting that electrons orbit the nucleus at specific distances
What did James Chadwick prove in the atom
The experimental work of James Chadwick provided the evidence to show the existence of neutrons within the nucleus. This was about 20 years after the nucleus became an accepted scientific idea
How did Rutherford’s gold foil experiment prove the atom was mostly empty space but with a positively charged nucleus in the centre
When they fired positively charged alpha particles at an extremely thin sheet of gold:
Most of the particles that were fire went straight through the empty space
Some were partially deflected showing the nucleus had a positive charge
Some were fully deflected showing there was a mass in the centre
What is the difference between the plum pudding model and the nuclear model
Plum pudding model: The atom is a ball of positive charge, plum pudding model is a ‘solid’ mass
Nuclear model: The nucleus in the centre was positively charged, most of the atom is empty space, most of the mass is in the centre
What does the mass number show
How many neutrons and protons the atom has
What does the atomic number show
The amount of protons
In an atom there is the same amount of electrons as ?
Protons
What is the overall charge of an atom
0
How to work out relative atomic mass
sum of (isotope abundance x isotope mass number) / sum of abundances of all isotopes
Properties of transition metals (typical metal)
Good conductors of heat and electricity
Dense
Strong
Shiny
