Chem AZX and AAM

what does the number of protons, neutrons, and electrons dictate?

which element is it, the atom’s mass, the atom’s neutrality, the atom’s nuclear stability

Aspects of the Bohr model

Electrons are on “rings” of different energy levels (made up of whole numbers), electrons have quantized energy (has to be a number value, not all electrons have the same value), protons and neutrons are very densely packed inside the nucleaus

Protons:

are subatomic particles with a mass of 1 amu, has a positive charge, located in the nucleus

Neutrons:

are subatomic particles with a mass of 1 amu, has a neutral charge, located in the nucleus

AMU

atomic mass unit

identity of an atom

atomic number; determined by proton count only

mass number=

protons+neutrons, measured in amu

Chemical reactivity

determined (in part) by ratio of protons:electrons. Atoms can be neutral, positive, or negative

A charged electron

an ion

neutral atom

an atom

Nuclear Stability

determined by ration of protons:neutrons (heavier element allows for greater difference in protons:neutrons)

AZX symbol

summarizes atomic info

what is the X in the middle for in the AZX symbol

element name

what is the A in the top left for in the AZX symbol

mass number (protons+neutrons)

what is the Z in the bottom left for in the AZX symbol

atomic number (protons)

what is the top right for in the AZX symbol

the charge (protons-electrons)

period

rows on the periodic table

family/group

columns on the periodic table

the design of the periodic table is based on two variables:

increasing atomic number, and repeating chemical properties

what do columns share

similar chemical properties

sections in the periodic table

s,d,p,f

Metals:

are in sections s,d,f, and some in p (outnumbers non-metals)

Non-metals:

are only in sections p (except for hydrogen)

what separates metals from nonmetals

a “staircase” on the periodic table

metalloids lie on:

the borders of the staircase

Metals properties:

lustrous, malleable, ductile, good conductors

Nonmetal properties

dull, brittle, bad conductors

Metalloid properties:

hybrid of metal and nonmetal (lustrous, bad conductors)

What happens when there is a more abundant isotope in one mixture

influences the average mass more

Average atomic mass formula (amu):

AAM= (% abundance of isotope A)(mass number of isotope A)+(% abundance of isotope B)(mass number of isotope B)+(etc.)