atomic structure - chemistry Flashcards
what did Rutherford’s alpha scattering experiment prove
atoms have a small dense nucleus with positive charge
how did Bohr adapt the model of the atom
he said electrons orbit the nucleus at specific distances
what did chadwicks work give evidence of
that the nucleus also contained neutrons as well as protons
What is the atomic number of an atom?
The number of protons in an atom
What is the mass number of an atom?
The number of protons + the number of neutrons in an atom
How do you calculate the number of neutrons in an atom?
Mass number - atomic number
How are the electrons arranged in atoms?
Orbiting the nucleus in shells
How many electrons can go in the first shell?
2
How were elements arranged in the early attempts of the periodic table?
By atomic weight
How are elements in the periodic table arranged?
By atomic number
What do you know about elements in the same group?
They have similar properties (reactions) as they have the same number of electrons in the outer shell
Why did Mendeleev swap the order of some elements?
So they were in the same group as elements they had similar chemical properties with
What is an ion?
an atom which has lost or gained an electron
What is the approximate radius of an atoms
0.1nm (1x10-10m)
How big is the radius of the nucleus compared to that of the atom?
1/10000 the size (so 1x10-14m)
