Atoms, Electrons, Orbitals 2 Flashcards
Single electron of hydrogen occupy _ orbital
1s
Two electrons of helium occupy a _ orbital
1s
Hydrogen and helium electron configurations written as _ (2)
H: 1s1 (1 above s)
He: 1s2
Spin quantum number of an electron can have a value of either _ or _
+ 1/2
-1/2
According to the Pauli exclusion principle, two electrons may occupy same orbital only _
When they have opposite spin
Opposite spin aka _
Paired spin
Because two electrons fill 1s orbital, third electron of lithium must _
Occupy orbital of higher energy
No orbital can contain
More than two electrons
Lithium electron configuration
1s22s1
Period of a periodic table corresponds to principal quantum number of _
Highest numbered occupied orbital (n = 1, etc.)
With beryllium (with 4 electrons) the _ becomes filled
2s level
Next orbital to be filled after 2s (beginning with boron) are (3)
2px
2py
2pz
2pxyz orbitals are of equal energy and are characterized by
Boundary surfaces described as dumbbell shaped
Axes of 2p orbitals are at
Right angles to each other
Regions (red and blue) of a single orbital may be separated by
Nodal surfaces
Nodal surface is where wave function changes sign and probability of finding an electron
Zero
With 2pxyz orbitals, each is singly occupied before _
Any is double occupied
The general principle for orbitals of energy is known as _
Hund’s rule
Countless organic compounds contain _ or both in addition to carbon (2)
Nitrogen
Oxygen
Most organic compounds also contain _
Hydrogen
Valence electrons in second row elements are _ electrons (2)
2s
2p
Because four orbitals (2s,2pxyz) are involved, max number of valence electrons in second row is
8
For main group elements, number of valence electrons is equal to _
Group number in periodic table (vII A)
