Chemistry Grade 11 Exam

cause why not

Bond polarity

the measure of how equally or unequally the electrons in any covalent bond are shared

Non polar

electrons are shared evenly ( EN diff = 0 - 0.4 )

Polar

electrons are unevenly shared ( EN diff = 0.5 - 1.7 )

Electronegativity

The ability of an atom in a molecule to attract electrons to itself- which can create a polarity

Dipole

A bond or molecule whose ends have opposite sides

Unsaturated Solution

A solution that can still dissolve more solute (at a given temperature). i.e: less than the maximum amount

Saturated Solution

A solution that has dissolved as much solute as possible.

• Any extra solute will just sit at the bottom and not dissolve

Super Saturated

A solution that contains more solute than normally possible.

• It is done by heating the solution, dissolving a lot of solute, then cooling it slowly

• It is very unstable~ a small disturbance can cause the extra solute to crystalize out

Factors that affect Solubility

• solute & solvent interactions

• temperature ( for solids/liquids )

• pressure ( for gaseous solutions )

Lattice Energy

The energy required to completely separate a mole of a solid ionic compound into its gaseous ions

• measures how strongly the ions are held together in crystal lattice

• the higher the lattice energy → the more stable and packed the solid

High lattice energy factors

→ Higher ionic charge

• A stronger attraction exists between more highly charged ions ( they have to give up TONS for the relationship so they aren’t quitting anytime soon )

→ Smaller ion size

• Smaller ions pack closely together, have less shells, and more protons so attractions are stronger

Isotopes

The same elements but different numbers of neutrons; therefore different masses

Radioisotopes

isotopes that are radioactive & unstable

• they emit radiation in the forms of particles and gamma rays

Average isotope weight // formula

7 Diatomics

H, N, F, O, I, Cl, Br

• occur naturally as molecules containing 2 atoms

• **MOLECULE = 1

• **ATOM = how many inside

Empirical vs Molecular

Empirical gives the lowest whole number ratio

Molecular gives the exact number of atoms

Nomenclature for BINARY acids:

Cation + Anion

→ change the anion ending from “ide” to “ic” and add Hydro:

HCl → Hydrochloric acid

Nomenclature for OXYacids:

Cation + Anion

→ If the anion ends in “ate” change ending to “ic”

**IF THERE’S AN O, DROP THE HYDRO

HClO₃ → Chloric Acid

3 types of reactions:

1. Combination

   • 2 or more substances react to form one product

   • 2Mg + O₂ → 2MgO

2. Decomposition

   • A product beaks down into 2 or more substances

   • CaCO₃ → CaO + CO₂

   • Many Metal Carbonates decompose to metal oxides and CO₂

3. Combustion

   • Rapid reactions that produce a flame

   • Most often involve oxygen in the air as a reactant

percent composition

% element = (# of atoms)(atom w of element)
		/  FW of compound

• this is different from percent by mass cuz ur probably given a specific amount of mass

Calculating Empirical Formula RHYME

% to mass

mass to mole

divide by small

multiply till whole

molecular formula whole # multiple =

molecular FW

—————

empirical FW

Define an electrolyte

An electrolyte is a substance that dissociates into ions when dissolved in water

STRONG ELECTROLYTE → dissociates completely

weak electrolyte → dissociates partially

non electrolyte →does NOT dissociate

Arrhenius Acids & Arrhenius Bases

Arrhenius Acids → H⁺

Arrhenius Bases → OH^-

Bronston Lowry acids are proton donors, and BL bases are all proton acceptors. Not all acids and bases are Arrhenius tho:

NH₃ + H₂O = NH₄ + OH^-

trick to distinguish acids and bases

**acids usually start with H ( HCl, H₂SO₄ )

**bases usually end with OH ( NaOH, CaOH₂ )

How to calculate FORMAL CHARGE

FC = V - B - L

; V = valence electrons

B = # of bonds

L = lone electrons

halogen reactivity

so since halogens are so close to being stable, they will go to any length to accomplish that

specifically, as you go up the column, reactivity increases because of the fewer electron shells, and higher effective nuclear charge.

Molarity Formula

M = n/v

Concentration to Dilution formula

M1 x V1 = M2 x V2

or

C1 x x V1 = C2 x V2

Effective Nuclear Charge Formula

Zeff = Z - S; Z is the atomic # [ number of protons or electrons ]

S is the screening constant aka INNER electrons

inner electrons = electrons - valence

Ionization energy

Amount of energy required to remove an electron

Electron affinity*****

Lewis dot charge rules

for negatively charged ions, add extra electrons to the NVE total

for positively charged ions, subtract extra electrons from NVE total

Metals & Nonmetals reaction predictions

Metal Oxides + Water = metal hydroxide

Metal Oxide + Acid = salt & water

Nonmetal oxide + Water = acid

Nonmetal oxide + Base = salt & water