Unit test #1 Flashcards
Binary compounds
Metals that only have 1 charge
-metal-non,criss cross simplify Ex: Berylium oxide BeO
Multivalent
-Metal has more ten 1 charge
-Roman numeral added
Ex: SnO2 Tin(IV) oxide
Polyatomic
-ending=ate or ite
- use brackets around poly atom
- Cu(SO3) 2 Copper(II) sulfite
Hydrate
-Water attacked to a crystal
-uses prefix to show the # of water molecules
-hydrate at the end of the name
Ex: CuSO4 . 5H2O
Copper(2) sulfate pentahydrate
Ionic compounds (nomenclature) rules
- if metal is multivalent find charge mathematically
1. eqaution= # of atoms of element x ion charge = total ion charge for anion
Cu l O 1 x -2=-2 switch sides
2/1= 2 Copper (II) oxide
Anhydrous
is compound formed from the hydrates remains in water is removed Ex: CaCl2
CoCl2 . 6H20
- Write a dot in between compound to show association
Acids
Binary: H + nonmetal or polyatomic ion that doesnt have O
1. H first then non metal
2. criss cross
3. Write (aq)
Ex: Hydrobromic acid
HBr(aq)
Oxyacid: H+ polyatomic ion with oxygen
1. H then polyatomic symbols
Note: -IC ending from ATE and OUS from ITE
2. criss cross cant be simplified
3.write aq
Ex; Chloric (ate) acid
HClO3 aq
what are Molecular compounds
Made up of 2 or more non metals sharing electrons in covalent bonds to make full octets
-can be solid,liquid or gas , low melting point and boiling,not easily dissolved in water
-uses prefixes to name change nonmetal ending to IDE
Electronegativity
The ability of an individual atom when bonded to attract bonding electrons to itself
- Higher the EN # the greated pull on shared electrons
- EN numbers can determine the type of bond (polar)
EN
-must calculate if ionic or molecular
- Greater EN more likely a bond us to be ionic and an electron transfer
Ionic bond: metal + nonmetal electron transferred
Polar covalent bond
- electrons spend more time with element with higher EN
- e- unequally shared
- and - poles in a molecule
+ pole represented by Delta +
- and - poles in a molecule
- pole represented by Delta -
Highest EN - lowest EN to find polarity
Ex:F-H
4.0-2.1=1.9
Non polar covalent bonds
- electrons are equally shared no poles
- EN must be less then 0.4 no deltas
Lewis structures steps
- Find a C.A (element with highest bonding capacity or lowest EN)
- Tve- : Add all valence electrons
if you have a polyatomic ion with a - charge u add 1 electron to your calculation if it has a + charge you take away an electron from calculation - Determine bond type by subtracting En for a polar or non polar bond
(ionic bond electrons transfer non metal +metal)
4.Draw the structure the bond represent 2 electrons if there is lone pairs on the C.A the structure bends.
Molecular polarity
- If asymmetrical= polar molecule
- if symmetrical = non polar molecule
- even if symmetrical but not a polar bond(no deltas) still a non polar molecule
Intermolecular forces
Forces of attraction b/w molecules
Ionic compounds (intermolecular forces)
- not made up of molecules
- hold formula units of crystal (electrostatic attraction)
- Solids always at room temperature
- strong so have high MP/BP
Molecular compounds
- strength of intermolecular forces determines physical properties (state of matter,MP/BP,surface tension)
- Room temp: mostly gases,few liquids(low BP) , solids melt easy means intermolecular forces are weak
- AS intermolecular forces increase in strength = MP/BP, surface tension increase
LDF
- very weak attraction
- easily broken and made up again
- Exists in all molecules
- Cause: shift in electron cloud for fractions of a second in a molecule and creates a temporary dipole
- Temporary dipole also forms in neighboring molecule and they now attract to each other
- larger the molecule =more e- & p
- Stronger the force = high melting point
Dipole Dipole
Force b/w oppositely charged ends of a polar molecule
Ex: H-Cl—–H-Cl (polar molecule)
- only seen in polar molecules
- Intermediate in strength
- the more polar the substance the stronger the dipole dipole force is
- these substances will have high BP/HP because of their intermediate strength
Hydrogen bond
- Very strong force when H is bonded to only N,O,F
- large EN difference
- small size of H
concentrates the positive pole which is able to easily
attract a negative pole of another close molecule
