Model Of The Atom 1.1.3 Flashcards
Who devised the plum pudding model in 1897?
J.J Thomson.
What is the plum pudding model?
A positively charged ball with electrons inside.
Who devised the nuclear model in 1909?
Ernest Rutherford.
What is the nuclear model?
The mass of the atom is concentrated in a nucleus.
The nucleus contains protons.
Who devised the modern model?
Niels Bohr.
What is the modern model?
Electrons orbit a positively charged nucleus at fixed distances.
Who discovered the neutron in 1932?
James Chadwick.
What charge does a proton have?
Positive, +1.
What is the atomic number a measure of?
Number of protons.
An element is defined by what?
It’s proton/atomic number.
What charge does an electron have?
Negative, -1.
The number of electrons is equivalent to…
The number of protons.
What charge does a neutron have?
Neutral, no net charge.
What is the mass of a proton and an neutron?
1.
What is the mass of an electron?
0.0005 (0).
Relative atomic mass is?
Number of protons and neutrons.
The average radius of an atom is?
About 0.1nm.
