HOW TO READ
DEFINITIONS
UNIT 2
UNIT 2 pt.2
ELEMENTS
100
group
each vertical column is called ___?
100
horizontal rows on the periodic table
What is the definition of period?
100
positively charged particles in the nucleus of an atom
what are protons?
100
neutral charge in atom
What is a neutron?
100
H
What is the chemical symbol for hydrogen?
200
alkali metals and halogens
What is in group 1 and 17?
200
most reactive non-metals group 17
what are halogens?
200
the electrons on the outer most ring of an atom
What are valence electrons?
200
protons + neutrons
what is atomic mass?
200
metalloid, which means it shares properties of both the metals and non-metals
What is silicon?
300
group 2 examples: Be , Mg , and Ca
what is group is alkaline earth metals? what are alkaline earth metals?
300
group 18 because they don't share their electrons
What are noble gasses?
300
the simplest model of an atom
what is a bohr model?
300
by AMU
what do you use to measure the atomic mass?
300
non-metal, which means it could be a solid, liquid, or gas and is a poor conductor of heat
What is carbon?
400
metalliods
What is the staircase on the right side of the periodic table?
400
characteristics that you can see through direct observation
what our physical properties?
400
subtract the protons from the mass and that is your number
how do you determine how many neutrons there are?
400
protons and neutrons
what is in the nucleus?
400
in the actinide series and has a symbol of Am
What is americium?
500
because its the only non-metal
what is hydrogen?
500
they can only be observed when one substance changes into a different substance
what are chemical properties?
500
it depends on how many electrons there are.
how do you determine how many energy levels there are?
500
most of the area of the atom
What is the electron cloud?
500
Boron
What is the symbol B stand for?
M
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