Chemistry chapter 8

 Electron configuration

  • An atom is a particular distribution of electrons amount the available subshell 

2.      Orbital diagrams

  • a diagram used to show how the orbitals of a subshell are occupied by electrons 

3.      Pauli’s exclusion principle

  • no two electrons in an atom can the same four quantum numbers

4.      Noble gas core

  • inner-shell configuration corresponding to one of the noble gasses

5.      Hund’s rule

  • the lowest-energy arrangement of electrons in a subshell is obtained by putting electrons into separate orbitals of the subshell within the same spin before pairing electrons 

  • Special: Cu:[Ar} 4s1 3d10 

  • Special Cr:[Ar] 4s1 3d5 

6.      Paramagnetic vs. diamagnetic properties of atoms

  • Paramagnetic: a substance that is weakly attracted by a magnetic field, and this attraction is generally the result of an unpaired electron 

  • Diamagnetic: a substance that is not attracted by a magnetic field or is very slightly repelled by such a field  

7.      Atomic properties like Atomic radius, ionization energies and electron affinities

  • Radius 

    • Period: radius tends to decrease with increasing atomic number

    • Group: radius increases with the period number

  • Ionization energy: within any period the value increase as the atomic number goes up 

    • First ionization energy, the amount of energy it takes to remove an electron from an atom within a gaseous state 

  • Electron Affinities

    • General trend is that the value increases from left to right, though 2A and 5A have smaller affinites, while group 8a has little to no affinity

    • Electon affinities, the energy required to remove an electron from an atoms negative ion or ground state

8.       Periodicity in main group elements.

  • Basic oxide: oxide that reacts with acids 

  • Acidic oxide: oxide that reacts with bases 

  • Amphoteric oxide: oxide that has both basic and acidic properties

  • Group 1(alkali metals ns^1)

    • reactivity increase as you go down the column

    • basic oxides 

    • formula of R2O

  • Group 2(alkaline earth metals ns^2)

    • reactive but much less than alkali (increases as you go down)

    • basic oxides

    • formula RO

  • Group 3 (ns^2np^1)

    • boron is a metalloid

    • all others are metals 

    • formula of R2O3

    • boron oxide (B2O3) is acidic

    • aluminum oxide (Al2O3) and gallium oxide (Ga2O3) are amphoteric

    • indium oxide (In2O3) and Thallium (Ti2O3) are basic 

  • Group 4(ns2^np^2)

    • Carbon non metal 

    • silicon And germanium metalloid

    • Tin and lead metals 

    • formula of RO2

    • Carbon dioxide (CO2), silicon dioxide (SiO2), and germanium dioxide (GeO2) is acidic

    • Tin dioxide (SnO2) lead(IV) oxide (PbO2) is amphoteric

  • group 5(ns^2np^3)

    • Nitrogen and phosphorus nonmetal 

    • arsenic and antimony metalloid  

    • bismuth metal 

    • empirical formula of R2O3 and R2O5

    • Molecular formula of R4O6 and R4O10

    • nitrogen (N2O3, N2O5), phosphorus (P4O6, P4O10), arsenic (AS2O3, As2O5) are acidic 

    • Antimony(Sb2O3, Sb2O5) is amphoteric

    • Bismuth(Bi2O3) is basic 

  • group 6(chalcogens nsnp^4)

    • Oxygen, sulfur, and selenium nonmetal 

    • tellurium metalloid

    • polonium metal 

    • Formula of RO2 and RO3

    • All except for TeO2 are acidic

    • PoO2 is amphoteric though more basic then TeO2

  • group 7 (halogens ns^2np^5)

    • reactive non metals 

    • molecular formula of X2 (X is a Halogen)

    • generally unstable acidic oxides 

    • Astatine might be expected to be a metalloid(have a very short half life)

  • group 8 (noble gasses ns^2np^6)

    • Unreactive