ionic bonding
1. What is an ionic bond?
2. What is the rule about who will attract or gain electrons?
3. Define cation and anion
1. An ionic bond is a chemical bond formed through the electrostatic attraction between OPPOSITELY CHARGED IONs. (bond created when one atom transfers one or more electrons to another atom)
2. Elements with higher e-negs are more likely to attract electrons (anion) whereas atoms with lower e-negs are likely to give them away (cation)
3. Cation = positively charged ion, loses e-
Anion = negatively charged ions, gains e-
1. Atomic radius - the smaller the radius, the higher the boiling point because small ions are closer together which means more attraction. more attraction = more energy need to separate the ions.
2. Ionic charge - the higher the charge, the higher the melting point because higher charge = more electrostatic attraction
what is polar covalent bond?
a non-metal unequally shares electrons w/ another non-metal. the atom with the higher e-neg value attracts the electron more than the atom with the lower e-neg value
1.) what is LDF, dipole dipole, and hydrogen bonding? How is boiling/ melting point related to imf?
1. ldf = temporary dipoles, very weak, lower melting/boiling point
dipole dipole = a dipole, no hydrogen bonding, medium strength
hydrogen bonding = dipole attached to hydrogen, oxygen or fluorine, srongest imf, higher melting / boiling point
Describe the following separation techniques:
Distillation Paper chromatography
Filtration Solvation
Recrystallization
Evaporation
Distillation: Separating liquids by boiling point
Paper chromatography: separates soluble colored substances based on how fast they move through paper.
Filtration: solid from liquid Solvation:
solute dissolves in a solvent, allowing certain substances to be separated based on solubility
Recrystallization: solid compound dissolve in hot solvent and then cooling, pure crystals form while impurities remain
Evaporation: solid from liquid by heating the liquid
2. How do you write equations between oppositely charged ions?
1. Group 1-13 form positive ions. Group 13-17 form negative ions
2. You balance the charges, then you balance the overall equation.
1. How does atomic radius increase and decrease, and WHY?
2. What is nuclear charge and how does it increase and why?
1. Atomic radius increases down a group due to added electron shells. It decreases across a period due to increasing nuclear charge.
2. Nuclear charge is the total positive charge of an atom's nuclear, determined by its number of protons.
increases from left to right due to added protons without increased shielding
what are exceptions in lewis dot structure?
2. What is a coordinate covalent bond
group 13 are exceptions, happy with six and not a full octet
period 3 and beyond can have more than 8 electrons in their valence shell
2. A coordinate covalent is when both of the shared electrons come from only one of the atoms involved in the bond rather than 1 electron from both
electrical conductivity of ionic bonds, covalent bonds, and metal
ionic compounds easily conduct electricity
covalent compounds do not contain ions and will not usually conduct electricity unless in some cases like acid and base
all metals conduct electricity due to their atomic structure, which features a "sea" of free, delocalized electrons that move easily through the metal's lattice. These free electrons, often valence electrons, can carry charge, making metals excellent conductors.
describe allotrope diamond
Diamond
tetrahedral 109.5 degrees
NH4 SO3 OH C2H3O2
NO2 SO4 PO4 HCO3
NO3 CO3 CN MnO4
NH4: +1, Ammonium
SO3: -2 Sulfite OH: -1 Hydroxide
C2H3O2: -1 Acetate
NO2: -1 Nitrite SO4: -2 Sulfate PO4: -3 Phosphate
HCO3: -1 Hydrogen carbonate
NO3: -1 Nitrate CO3:-2 Carbonate
CN: Cyanide -1 MnO4: Permangranate -1
1. what happens to a lattice structure when placed in water?
1. Dissolution (breaking apart of the lattice) seperated and dispersing througout the water due to water's polarity
2. Each ion gets surrounded by water molecules in a process called hydration, stabilizing them in the solution.
3. Overall process either releases or absorbs heat.
lattice energy greater than hydration = endothermic
lattice energy lower than hydration = exothermic
Write the angle and details for each of these shapes?
Linear Tetrahedral
Trigonal pyrmamidal
Trigonal planar Bent 2
Bent
Tetrahedral
Linear- 180 degrees, 2 bonds no lone pairs
Trigonal pyrmamidal - 107.5 degrees, bonded to 3, 1 lone pair
Trigonal planar- 120 degrees, bonded to 3, no lone pair
Bent- 118 degrees, bonded to 2 elements, 1 lone pair
Tetrahedral- 109.5 degrees, bonded to 4, no lone pair
Bent 2 - 105.5 degrees, bonded to 2 elements, 2 lone pairs
where are metals?
1. metallic bonding - metal atoms release electrons into a "sea" that holds the metal together
they are left/ center of periodic table, have luster, conduct heat/ electricity, are malleable and lose electrons to form cations
describe allotrope graphite
Graphite:
Trigonal planar - 120 degrees
Melting point: Very high (above 3500°C)
Graphite has layers of carbon atoms, which is why it is used in pencils.
2. What is a coordination number?
1. It is called a lattice structure. The big circles are the negative ions, and the smaller circles are the positive ion.
2. A coordination number is the number of neighboring ions of opposite charge surrounding a single ion (2,4, 6)
what is a covalent bond?
a covalemnt bond is when a non-metal shares electrons with another non-meta to achieve an octet (like a noble gaS)
the shared eelctrons are held between the nuclei and attracts both atoms using electrostatic attraction
what is the difference in e-neg and what does it indicate?
0 - 0.4 = covalent
0.4 - 1.6 = polar covalent
1.6+ = ionic
2. The charge of the metal : the greater the charge, higher the strength
2. Radius of the cation: the smaller, the greater the strength
describe allotrope fullerene
Spherical
2 single bonds in petagons (180 degrees) or double bond 120 degrees in hexagons
How do you describe a lattice structure?
1. State the coordination number (opppositely charged), mention that each ion is surrounded by many surrounding ions
2. Mention the 3D repeating lattice (repeats in 3 dimensions)
3. Connect it to stability: maximizes electrostatic attraction resulting in a stable ionic structure
describe a single bond vs a triple bond
A single bond (2 electrons, 1 pair) Weakest strength, longest length, less reactive
A triple bond (less bonds) is 6 electrons, strongest bond length, highest energy, most reactive
Bond length lowers with increased bonds, bond strength increases with more bonds
what is symmetry and how does it affect bond dipoles
if the molecule is symmetrical and the bond angles are equal and opposite, they cancel and the molecule is non polar
describe PV=nrt, what conversion should they be in
P= pressure, kpa 101 kpa = 1 atm
V= volume, liters
n= mols, n
r= gas constant, 0.0821
T= temperature, kelvin 0 degrees celsius + 273 K
describe allotrope graphene
2-D sheet
120 degrees