The nucleus ..
is in the middle of the atom and contains protons and neutrons. It has a positive charge.
The total number of protons and neutrons.
Electrons ...
...move around the nucleus in electron shells and is negatively charged. Electrons are tiny!
...are useful for the hydrogenation of alkenes.
The mass of a proton is ...
1
2
3
The mass of a neutron is ...
0
The mass of an electron is ...
5
0.5
0.0005
The charge of a proton is ...
+2
+1
The charge of a neutron is ...
The charge of an electron is...
-1
Who concluded from his experiments that atoms weren't solid spheres?
J J Thomson
John Dalton
Rutherford
Bohr suggested that electrons can only exist in _?_, or _?_.
nuclear atom | particle
fixed orbits | energy
fixed orbits | shells
