Atoms and reactivity
The number of electrons allowed in the first shell
What is two
The element with the symbol O
What is oxygen
How the periodic table is organized
What is by atomic number
What are protons and neutrons
How many energy shells hydrogen has
What is 1
The number of electrons allowed in the third shell
What is eight
The element with the symbol S
What is sulfur
The number of electrons in an atom comes from this
What is the number of protons / atomic number
What are energy shells
How many energy shells sodium has
What is 3
If sodium loses an electron its charge becomes
Positive 1
The chemical symbol for Sodium
What is Na
A horizontal row is called this
What is a period
Subatomic particle that makes up electrons
What are leptons
The number of valence electrons magnesium has
What is 2
If oxygen gains two electrons the charge becomes
The chemical symbol for Gold
What is Au
This changes as you move down a group (column)
What is have unpaired electrons, not a full outer shell
The number of valence electrons krypton has
What is 18
If an atom gains/loses electrons it becomes this
What is an ion
The chemical symbol for Tungsten
What is W
The name of the group that is not reactive at all
What are noble gases?
This scientist created an accurate model of the atom
How sodium and chlorine form a compound
Sodium gives one electron to chlorine