REVIEW CLASS FOR NOVEMBER 7, 2007
#1) DURING BONDING POTENTIAL ENERGY DECREASES IN ALL
BONDING, BOND FORMATION IS EXOTHERMIC ALWAYS ---(1)
N + NN
#2)
2 THE TWO N ATOMS COMBINE(BOND) TO FORM
N2 THEREFORE A BOND IS FORMED AND ENERGY IS RELEASED
(EXOTHERMIC) --(4)
#3) ACCORDING TO TABLE “S”, Na has the smallest value for
electronegativity. Also group one metals are low in electronegativity. –(1)
#4) ACCORDING TO TABLE “S” SULFER (S) HAS THE HIGHEST
ELECTRONEGATIVITY ---(3)
#5) OXYGEN IS THE MOST ELECTRONEGATIVE AND WOULD EXERT THE
GREATEST ATTRACTION FOR THE ELECTRONS. – (2)
#7) BASED ON IONIC CHARACTER (1.9), MgCl2 IS IONIC. Also Mg is a
metal from the left and S is a nonmetal. – (1)
#8) GROUP ONE METALS CAN ONLY BOND IN IONIC BONDING. Na IN
Na2O IS IN GROUP ONE. ALSO THE IONIC CHARACTER BETWEEN Na
AND O IS 2.6, WHICH IS IONIC. --- (2)
#9) THE GREATEST IONIC CHARACTER (1.9) IS IN HF ..(2)
#10) NaF, NOTICE ALL AR BONDED TO F, THERFORE THE LEAST
ELECTRONEGATE METAL WILL HAVE THE GREATEST IONIC
CHARACTER.
#11) HI HAS THE LEAST IONIC CHARACTER BASE ON TABLE “S”
ELECTRONEGATIVITIES – (4)
#12) Sr IS A GROUP TWO METAL, METALS LOSE ELECTRONS WHICH
MEANS THE ION IS POSITIVE AND HAS FEWER ELECTRONS THAN THE
ATOM, THE ATOM HAS A GREATER NUMBER OF ELECTRONS –(1)
#13) CHRYSTALLINE AND CONDUCTIVE IN THE THE MELTED STATE ARE
IONIC CHARACTERISTICS –(1)
#14) IONIC LIQUIDS ARE CONDUCTORS, NaCl (aq) IS SUCH A SUBSTANCE
(BASED ON IONIC CHARACTER IT IS IONIC). ALSO ALL GROUP ONE METAL
SALTS (Na IN THIS SALT) ARE SOLLUBLE AND CONDUCTIVE. –(2)
#15) THE LEAST IONIC CHARACTER IS CO2, -- (1)
#16) THE TRANSFER OF ELECTRONS OCCURS ONLY IN AN IONIC BOND.
Na2O IS THE ONLY IONIC SUBSTANCE (IONIC CHARACTER IS 2.6, AND
Na IS IN GROUP ONE WHICH INDICATES AN IONIC COMPOUND)—(4)
#17) NON POLAR COVALENT BONDS ARE EQUALLY SHARED
ELECTRONS BY DEFINITION. –(3)
#18) F2 IS IN H2, O2, N2, Cl2, Br2, I2, F2 WHICH ARE ALL NONPOLAR
(BONDED TO ONE OF ITS OWN ELEMENT TYPE, IONIC CHARACTER =0
FOR THE BOND)---(2)
#19) IONIC CHARACTERS BELOW 1.7 ARE COVALENT, WHERE
ELECTRONS ARE SHARED ---(3)
#20)
Cl
H
Cl H
#21) THE IONIC CHARACTER BETWEEN H AND Br IS 0.90, WHICH IS
POLAR COVALENT ( FROM ABOUT .4 UP TO 1.7)—(2)
#22 THE IONIC CHARACTER BETWEEN O AND H IS 1.4, WHICH IS VERY
POLAR AND COVALEN -- (4))
#23)--(4)
#24)--(4)
H
H
N
H
+
BOTH OF THESE ELECTRONS
ARE FROM THE NITROGEN;
WHEN ONE ATOM CONTRIBUTES
BOTH ELECTRONS IT IS CALLED
COORDINATE COVALENT
BONDING
H
BOTH N AND H CONTRIBUTE
ONE ELECTRON, THIS IS A
COVALENT BOND, POLAR DUE
TO A N TO H IONIC CHARACTER
OF 0.9.
#25)CARBON DIOXIDE HAS AN IONIC CHARACTER OF 0.9, WHICH IS
COVALENT AND ALL COVALENT BONDS FORM MOLECULES
(MOLLECULAR).—(1)
#26) NaCl IS IONIC (Na is in group 1), Cu(s) is metallic, KF is ionic.
C6H12O6 all bonds are covalent.
C-O is 0.9, H to O is 1.4, and H to C is 0.5: all covalent!—(2)
#27) COVALENLY BONDED COMPOUNDS ARE NEVER CONDUCTIVE,
SOFT AND MOLECULAR – (1)
#28) By definition it is covalent network solid, --(1)
#29) THE ONLY SOLID CONDUCTORS ARE METALS (SEA OF
ELECTRONS) –(1)
#30) THE ONLY SOLID CONDUCTORS ARE METALS (SEA OF
ELECTRONS)AND CALCIUM IS THE ONLY METAL HERE! –(3)
REVIEW CLASS PAGE 4:27
#1) CH4 IS TETRAHEDRAL (RECOGNISE CENTRAL CARBON WITH 4
SINGLE BONDS, NO ELECTRON PAIRS). THIS IS SUMMETRICAL –(2)
#2) H2O IS POLAR DUE TO THE CENTRAL OXYGEN HAVING 2 BONDS
AND TWO ELECTRON PAIRS – BENT GEOMETRY WHICH IS
ASYMETRICAL. – (3)
#3) THE SMALL AND ELECTRONEGATIVE CENTRAL ATOM IS ABLE TO
GRAB A LARGE SHARE OF THE ELECTRONS IN THE BOND – (3)
#4) H2O HAS THE GREATEST IONIC CHARACTER, SEE BELOW.—(2)
HIGH IONIC
CHARACTER
MORE UNEQUAL
SHARING OF
ELECTRONS
GREATER
POLARITY
STRONGER
ATTRACTIONS
#5) HYDROGEN BONDING ATTRACTIONS OCCUR IN COVALENT
MOLECULES WHERE HYDROGEN IS BONDED TO F,O,N IN
ASYMETRICAL MOLECULES.
#6) DISPERSION FORCES (Van der Waals) are strongest in particles with
the largest molar mass.Theyare weakest in particles with the smallest
molar mass. He (4.0 g/mol) is the lightest of these and has the weakest
dispersion forces. Xe would have the strongest, molar mass 131.1
g/mol)—(4)
#7) H2 is nonpolar, and had dispersion forces as do all non-polar
substances. (4)
#8) DISPERSION FORCES WEAKEN AS PARTICLES BECOME LIGHTER.
IN TERMS OF MOLAR MASS Xe>Kr>Ar>Ne, THIS DECREASE IS ALSO
THE ORDER OF STRENGHT OF DISPERSION FORCES, WHICH DECLINE
–(4)
#9) DISSOLVING IS THE ATTRACTION OF A METAL ION TO WATER
MOLECULES –(2)
#10) Ca IS A METAL FROM GROUP 2, IT IS AS AN ION Ca+2 , WHICH
ATTRACTS TO THE NEGATIVE POLE OF WATER WHICH IS OXYGEN—(1)
#11) KCl IS IONIC, DISSOLVES BY MAKING MOLECULE TO ION
ATTRACTIONS – (3)
#12) MOLECULE TO ION –DISSOLVING.
#13)(1)
#14) MOLECULE-ION ATTRACTIONS (DISSOLVING) ARE FOUND IN
AQUEOUS SOLUTIONS OF IONIC SUBSTANCES, IN THIS CASE KCl (AQ)(4)
#15)POSITIVE ION
ATTRACTS TO NOGATIVE
POLE, O.—(4)
+
-
#16) MOLECULE-ION ATTRACTIONS (DISSOLVING) ARE FOUND IN
AQUEOUS SOLUTIONS OF IONIC SUBSTANCES, IN THIS CASE NaCl
(AQ)-(1)
#17) CHEMICAL FORMULAS REPRESENT BOTH ATOMS AND
COMPOUNDS.
#18) THE MOST REDUCED SUBSCRIPTS REPRESENT AN
EMPIRICAL(SIMPLE) FORMULA, K2O IS IN MOST REDUCED FORM –(1)
#19) THE MOST REDUCED SUBSCRIPTS REPRESENT AN
EMPIRICAL(SIMPLE) FORMULA, CH4 IS IN MOST REDUCED FORM –(1)
#20) THE MOST REDUCED SUBSCRIPTS REPRESENT AN
EMPIRICAL(SIMPLE) FORMULA, CH2O IS IN MOST REDUCED FORM –(4)
#21) THE MOST REDUCED SUBSCRIPTS REPRESENT AN
EMPIRICAL(SIMPLE) FORMULA, H2O IS IN MOST REDUCED FORM –(2)
#22) THE MOST REDUCED SUBSCRIPTS REPRESENT AN
EMPIRICAL(SIMPLE) FORMULA, P2O5 IS IN MOST REDUCED FORM OF
P4O10 --(3)
#23) LEAD
(11) = Pb+2
Pb+2 (PO4)-3
#24)
Pb3 (PO4)2 --(3) CRISS-CROSS
Ca+2 CAUSE IT IS IN GROUP 2
Ca+2 (PO4)-3
Ca3 (PO4)2 --(4) CRISS-CROSS
#25) FROM TABLE E, NO3- NITRATE AND ClO3- CHLORATE BOTH
HAVE OXYGEN.
#26)
N+1 O-2 N2O --(2) CRISS-CROSS,REMENBER O-2 IS OXIDE