General Chemistry

Trigonal bipyrimidal

• 
• e.g. Sulfur tetrafluoride

Disproportionation reactions

Ex.

2H₂O₂(aq) --> 2H₂O(l) + O₂(g)

Peroxide molecule (-1 oxidation state) separates into water (-2 oxidation state) and molecular oxygen (0 oxidation state).

It is a species that can donate one or more protons.

These are species that can accept an electron pair (acid) or donate an electron pair (base).

The Henderson-Hasselbach equation.

• A^- = conjugate base
• HA = weak acid
• pK_a = acid dissociation constant

For aA + bB ----> products

Rate = k[A]^m [B]ⁿ (in Molarity/unit time)

• k = rate constant (units vary with temp)
• m & n = reaction order
• A & B = concentrations (M)

Note: m≠a & n≠b   ***

22.4 L

1. The partial pressure of a gas is proportional to its mole fraction in the mixture.

P_A = X_AP_tot   where P_A is the partial P of gas A (X_A is its molar fraction)

2.  The total P of a system is equal to the SUM of the partial Ps of the substances in the mixture.

3.  The parital P of one gas in a mixture is independent of the other(s) in the mixture.

It is a release of a photon from an element in a nuclear excited state (parent marked with a *), resulting in no change in charge, mass, or atomic number.

To the right and up along the periodic table.

• - Thus, F has the highest electron affinity.
• - Negative enthalpy (-ΔH) --> FAVORABLE!

PV = nRT

• First letter - main element
• Consonants - number of oxygens
• Vowels - number of negative charge

1. All salts of alkali metal ions (e.g. Group IA elements --> Li, Na, K, Rb, Cs, Fr) are water-soluble.

2.  All salts of ammonium (NH₄⁺) are water-soluble.

• 3.  All salts with Cl^-, Br^-, I^- are water soluble
•    Except for salts containing Ag⁺, Pb²⁺, and Hg₂²⁺

• 4.  All salts of SO₄^2- (sulfate) ion are water soluble.
•    Except for those containing Ca²⁺, Sr²⁺, Ba²⁺, and Pb²⁺

• 1.  All metal oxides (a metal combined with oxygen) are insoluble,
•    Except for:
•    a) alkali metal oxides, and
•    b) CaO, SrO, BaO <-- hydrolyze to form solutions of corresponding metal hydroxides.

• 2.  All hydroxides (containing OH^-) are insoluble,
•    Except for:
•    a) alkali metal hydroxides, and
•    b) Ca(OH)₂, Sr(OH)₂, Ba(OH)₂

• 3.  All salts with the ff are insoluble:
•      (1) carbonates (CO₃^2-)
•      (2) phosphates (PO4^3-)
•      (3) sulfides (S^2-)
•      (4) sulfites (SO3^2-)

• Except for those containing:
•    a) alkali metals, or
•    b) ammonium (NH₄⁺)

1.  A free element (elemental state) has an oxid. number (O.N.) of 0.

• 2.  The oxidation number of a monoatomic ion equals charge of the ion.
•    Ex. Na⁺, Cu²⁺, Fe³⁺, Cl^-, N^-3- --> +1, +2, +3, -1, -3 resp.

• 3.  O.N. of a group IA element in a compound is +1;
•     for group IIA elements in a compound, O.N. is +2.

• 4.  O.N. of Group VIIA elements in a compound is -1;
•    except: when combined with an element with higher electronegativity.
•    ex. HCl: O.N. of Cl is -1
•         HOCl: O.N. of Cl is +1 (oxid. state of oxygen is -2).

• 5.  O.N. of H is +1 (most common);
•    except: when combined with less-electronegative elements (Groups IA and IIA) --> O.N. is -1.
•    ex: NaH and CaH₂ (oxid. state of H is -1)

• 6.  O.N. of oxygen is -2;
•    except: when combined with a more electronegative element (e.g. OF₂) --> O.N. of oxygen is +2 (F is more E_N, thus has oxid. state of -1).

•    ex. OF₂ (oxid. state of F is -1), O.N. of oxygen is +2
•         Peroxides (e.g. BaO₂), O.N. of oxygen is -1 instead of -2 (Ba can't have oxid. state of +4)
•           note: peroxide [O-O]^-2 Ba²⁺

7.  Sum of all O.N. of all atoms in a neutral compound is 0.

8.  Fluorine has O.N. of -1 in ALL compounds (F is most electronegative).

• 9.  Metallic elements only have positive O.N.; however:
•      non-metallic elements may have positive or negative O.N.

• R = 0.0821 L·atm/mol·K
• R = 8.3145 J/mol·K

1 atm = 10⁵ Pa = 760 mmHg = 760 Torr

• HClO₄     (perchloric acid)
• HCl         (hyrochloric acid)
• H₂SO₄     (sulfuric acid)
• HNO₃      (nitric acid)

• NaOH     (sodium hydroxide)
• KOH       (potassium hydroxide)
• Ca(OH)₂ (calcium hydroxide)

- other soluble hydroxides of group IA and IIA metals.