Elements
These are examples of the elements what?
O, Na, K, Au, Ni.....
Atomic Symbol/ Element Symbol
compounds need what and need to be what in order to be considered a compound
need to be atoms of two or more different elements
joined together by chemical bonds
These are a combination of two or more pure substances that are not chemically combined?
mixture
on the periodic table the categories that are vertical are called what?
groups or families
Which two elements on the periodic table are liquids at room temperature?
Mercury and Bromine
This is the basic unit of a chemical element
Atom
These consist of two or more atoms of the same element
molecules
how are mixtures able to be separated?
Physically
the categories on the periodic table that run left to right like sentences are called what?
periods
B, Si, Ge, As, Sb, Te, Po, At
These are the subatomic particles that make up an Atom
proton, neutron, and electrons
These can only be seperated by chemical means, not physically
Compounds
This is the item that is being dissolved in a solvent ex. kool aid, lemonade mix, nesquick, sugar
solute
These are the outermost energy levels of an element, each group has the same amount of them
valence electrons.
Which families are radioactive?
Lanthanides and actinides
These two subatomic particles are what give the element its number
Proton or electron
Which of these examples is a compound
H20 H4
C2 NaCl
CO2 Au
H2O, NaCl, CO2,
When the mixture is mixed up in an even distribution it is considered what?
homogenous
as you move down the periods, what increases?
the energy level or the shells.
What do the lewis dot diagrams tell you about the element?
The amount of electrons in its last shell
In order to find the elements neutron count you need to do what?
Subtract the atomic number from the atomic mass
Atomic mass - atomic number = neutrons
molecule
when you have a solvent and solute mix you are making a what? ex. sugar and water
solution
what are the 3 main sections that elements are separated into ?
metals, nonmetals, and metalloids.
What happens to the noble gases when you run electricity through them?
They glow
As you have more electrons, what levels increase?
The energy levels.
When the mixture is not uniformly mixed, it is considered what? ex. sand and water
heterogenous
This group has a full shell and is non reactive
noble gases or group 8
Who was it that created the first periodic table?
Dmitri Mendeleev
Consists of only one kind of atom
Element
When you have an alloy like bronze, steel, or brass, are these considered compounds or mixtures?
they are mixtures. they can be separated physically
name three ways that the periodic table follows to organize elements
either: atomic mass, atomic number, valence electrons, reactivity, periods, groups/ families
Draw the lewis dot diagram of these 3 elements
1. period 3, group 5
2. period 5, group 1
3. period 6, group 8
P.
Rb
Rn