Atomic And Nuclear Physics Flashcards
What was the atom nicknamed early on
Plum pudding
What is an alpha particle?
An alpha particle aid the same as the nucleus of a helium atom, ie. 2 protons (+) 2 electrons.
What does it mean If alpha particles pass through a thin gold foil?
Most of the atom is made up of empty space and the nucleus is very small
What does it mean if alpha particles are deflected off a gold foil?
The atoms are positively charged
If they are deflected backwards (backscattering) it means that the nucleus contains most of the atoms mass, it is very small and dense.
What are Electrons;
Charge
Mass
Position in the atom?
-1
1/1840
Shells
What are protons;
Charge
Mass
Position in atom?
+1
1
Nucleus
What are neutrons;
Charge
Mass
Position in the atom?
0
1
Nucleus
How many protons and neutrons does lithium have?
7
LI
3
3p +4n —->7
LI
3 protons—>3
Label this diagram of a nucleus
z
X
y
X = chemical symbol Z = atomic mass number (number of protons and neutrons) y= atomic number (number of protons)
The neutron number (N) = z-y
What is an isotope?
A different version of an element written with the same number of protons but a different number of neutrons
Some atoms have combinations/ratio of protons which makes their nucleus very unstable. (They have too much energy)
What does this mean?
This means the nuclei will emit nuclear radiation in an attempt to become more stable, they are said to be RADIOACTIVE.
What are the three types of nuclear radiation which come naturally from isotopes?
Alpha
Bet
Gramma
What is an alpha particle?
An alpha particle is the same as a helium nucleus, consisting of 2 protons and 2 neutrons.
What is a beta particle?
A beta particle is the same as a very fast electrum.
What is gramma?
Gramma radiation is not a particle but a high energy electro-magnetic wave.
