Atoms and Molecules Flashcards
mass of protons
1.673 x 10^-27kg
mass of neutrons
1.675 x 10^-27kg
mass of electrons
0.00091 x 10^-27 kg
atomic number
number of protons present in the atom
list the metalloids
astatine
germanium
boron
silicon
group 1a
alkali
group 2a
alkali earth metals
group 7a
halogens
group 8
noble gases
cations
positively charged atoms
anions
negatively charged atoms
atomic mass
the abundance weighted average of the mass number of each naturally occurring isotope
what do the solutions of Schrodinger’s equation define
volume in space where it is most likely to find one electron
what are the 4 quantum numbers?
- principal quantum number
- angular momentum quantum number
- magnetic quantum number
- spin quantum number
principal quantum number
determines the overall size and energy of the orbital: corresponds to the period number
angular momentum quantum number
the shape of the orbital, energy
magnetic quantum number
orientation of the orbital
spin quantum number
indicates the direction of the electron spin (+/- 1/2)
how do electrons arrange themselves?
electrons occupy free orbitals before filling one to minimize charge repulsions
what happens to the atomic radius along a period?
decreases as a result of the increasing nuclear charge
what happens to the atomic radius down a group?
increases because the electrons occupy larger regions in space
avogadro’s number
6.02214 x 10^23
mole
in 12g of 12C there are 6.02214 x 10^23 atoms of carbon
equation of moles
moles = mass/molar mass
number of atoms equation
number of atoms= number of moles x avogadro’s number
