P4 Revision Flashcards
Approximate for the radius of an atom
1 x 10^-10 metres
3 sub-atomic particles
Proton
Electron
Neutron
Where is mass most concentrated in the atom
Nucleus
How does the ratio of electrons to protons in an atom result in the atom having no overall charge
Number of protons is equal to number of electrons
What do all forms of the same element have in common
They have the same number of protons
What is the name for number of protons in an atom
Atomic number
What is an atom’s mass number
Number of protons and neutrons in an atom
What is an isotope of an atom
An atom of an element of an that has a different number of neutrons but same number of protons
Plum pudding model
Ball of positive charge with negatively charged electrons distributed evenly throughout it
Alpha scattering experiment
Alpha particles fired at gold foil
Most particles pass straight through
Small number deflected
Small number came straight back off foil
Alpha scattering experiment results
Atom mostly space
Concentration of positive charge in the atom
Concentration of positive charge is in a tiny volume
Why do unstable nuclei give out radiation
-to become more stable
-their stability increases
