30 terms

Chemistry Midterm GES 105

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Any material that is made up of only one type of atom is classified as
an element
The periodic table lists more than
100 elements
The origin of the elements is
the stars
What is known about atoms is that they are
perpetually moving, tinier than the wavelengths of visible light and recycling among innumerable forms.
What is known about atoms is that they are
mostly empty space.
A protons charge is
positive
A neutrons charge is
neutral.
A electrons charge is
negative.
The symbol Co is the element
Cobalt
CO2 is
carbon dioxide
The atomic number os an elements matches
the number of protons in the nucleus of the atom.
Noble or inert gasses are in group
18.
Noble and inert gasses's atoms have
similar properties and are unreactive.
The radioactive decay of nature's elements occurs
all around us.
Helium nucleus with +2 charge, most ionizing, least penetrating
Alpha Radiation
high speed electron, negative charge moderate penetrability
Beta Radiation
non-ionizing, no mass, highest penetrability
Gamma Radiation
Radon is a gas at
Temperature and pressure.
When food is exposed to gamma radiation, the food is
safe to eat
A certain isotope has a
half life of one day
This means the amount of that isotope remaining at the end of four days will be
1/16th
When an element ejects an alpha particle, the mass number of the resulting element reduces by
4
Attractions between molecules goes up as temperature
goes down
Maximum attraction is found in
solids.
Moderate attraction found in
liquids.
Least attraction found in
gasses.
A physical change is a change of
State of Matter. (ex. solid & liquid)
A chemical change is when atoms in the reactant molecules
break apart and form new molecules.
A compound contains different
atoms bonded together.
A mixture contains
more than one kind of atom and molecule.