This is the smallest piece of an element that still has the properties of that element. It comes from the Greek word for "uncuttable".
What is "atom"?
This particle has a charge of +1.
What is a proton?
The horizontal rows of the periodic table are called these.
What are periods?
What are electrons?
The masses of atomic particles are measured using this unit.
What is the atomic mass unit?
J.J Thompson discovered these curious particles that have a negative charge with his famous cathode ray experiment.
What are "electrons"?
What is the electron?
The vertical columns of the periodic table are called these.
What are columns?
These are the most reactive metals with just 1 electron in their outer shell.
What are the alkali metals?
What are the Group 1 metals?
This particle has an atomic mass of 0.
What is the electron?
What are protons?
What is 0?
The periodic table is arranged according to this.
What is atomic number?
These are the most reactive non-metals.
What are the halogens?
What are the Group 17 elements?
Isotopes are atoms of the same element that have different numbers of these.
What are neutrons?
Rutherford discovered this with his famous gold foil experiment. Nearly all of the atom's mass is found here.
What is the nucleus?
Normally, an atom has an overall charge of this.
What is 0?
When this becomes filled, you start a new row in the periodic table.
What is the electron cloud/shell?
These are the second most reactive metals but are still so reactive you do not find them in their pure form in nature.
What are the alkaline-earth metals?
What are the Group 2 metals?
Atoms with the same this are all the same element.
What is atomic number?
What is the number of protons?
This is the number assigned to the total number of protons and neutrons found in the nucleus of an atom.
What is mass number?
If your atom has 6 protons and 8 electrons, then your atom has an overall charge of this.
Elements in the same this usually share the same properties.
What is group/family?
These are the least reactive elements in the periodic table due to their completely filled outer shell.
What are the noble gases?
What are the Group 18 elements?
This is the first man made element on the periodic table.
What is element 95?
What is Americium?