Lesson 3 (M3) & (M5) - How atoms differ & the periodic table Flashcards
What is an atomic number?
The amount of protons in an atom.
Atomic number = ?
= number of protons
= number of electrons
Isotopes
Atoms with the same number of protons but different number of neutrons.
What do groups 1-2, and 13-18 have?
Representative elements.
What are group 3-12?
Transition metals.
Metal properties
Shiny, smooth, solid at room temperature, and good conductors of heat and electricity.
Alkali metals
Group 1 (in exception of hydrogen), very reactive.
Alkaline metals
Group 2, are highly reactive but moderate when compared to group 1.
Non-metal properties
Gases or brittle, dull-looking solids. They are poor conductors of heat and electricity.
Group 17
Highly reactive, called halogens.
Group 18
Extremely unreactive. Commonly called Noble gases.
Metalloid properties
Metalloids have properties of both metals and non-metals.
What is an Ion?
An atom or molecule that has an electric charge
(either positive or negative)
What is Ionization energy?
Ionization energy measures the tendency of an atom to resist the loss of its valence electron
The octet rule states that
Atoms lose, share, or gain electrons to acquire a full set of valence electrons