Atoms, Molecules and the Periodic Table Flashcards
Final Exam Content
Atom definition
The smallest unique species of an element.
Atomic scale name
Angstrom
Angstrom value
1 Å = 10^-10m
Prefixes from small things
m = 10^1
mm = 10^-3
μm = 10^-6
nm = 10^-9
pm = 10^-12
fm = 10^-15
Prefixes for large things
m = 10^0
km = 10^3
Mm =10^6
Gm = 10^9
Tm = 10^12
Pm =10^15
Dimensional analysis process
desired unit = current unit x conversion rate.
rearrange the conversion rate so you have a fraction equal to 1.
Substitute in conversion rate.
Why is angstrom used in chemistry
The radius of an atom ranges on the Angstrom scale, which means that chemists get their own unique measuring scale.
Why is dimensional analysis important
It makes transferring between different units easy.
number of atoms in a substance formula
number of atoms = (mass of substance) / (mass of one atom)
Atomic Mass Units (amu) to kg
1amu = 1.661 x 10^-27kg
kg to Atomic Mass Units (amu)
1 kg =6.02 x 10^26 amu
The Avogadro Number
L= 6.02 x 10^23amu
The Avogadro Number definition
The number of species within a mole.
Number of atoms in a substance whole calculation
mass of one atom in kg = RAM amu x 1.661 x 10^-27kg/amu.
# of atoms = mass of substance / mass of one atom.
mass of a proton
1.0073 amu
mass of a neutron
1.0087 amu
charge of a proton
+1.6 x 10^-19C
relative charge = +1
charge of an electron
-1.6x 10 ^-19C
relative charge = -1
nuclide notation
A over Z then chemical symbol
A = mass number
Z = atomic number
mass number
The mass of the protons + the mass of the neutrons.
mass number = 1.0073(#protons) + 1.0087(#neutrons)
atomic number
The number of protons in the nucleus.
RAM of an element calculation
RAM = (%abundance y) x (isotope y RAM) + (%abundance z) x (isotope z RAM)
Isotope definition
An atom of the same element with the same atomic number but a different mass number.
Nuclear binding energy definition
The energy required for the nucleus of one atom to be disassembled into its protons and neutrons.