av Baig Sohail 12 måneder siden
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n = m/M
c1v1 = c2v2
C = n/v
'Spectator Ions' removed Spectator Ions are ions that don't appear on both sides of the equation
Each Ion separated
Two liquids mix, one solid (precipitate)
Dilution Formula: C1V1 = C2V2
Diluting a stock solution of HCL(aq)
- Add 250mL or more of distilled water up to the fill line
- Measure and add 250 mL of HCL (aq) to volumetric flask
- Add approx. 500 mL of distilled water to volumetric flask
- Obtain 1000mL volumetric flask
Creating 500 mL of a mol/L of NaOH
- Obtain 500mL volumetric flask
- Add 250 mL or more to reach the fill line
- Cap and invert to mix
- add approx. 250 mL of distilled water to flask
- Place measured amount of solid in flask
Concentration = # of moles/volume or (c = n/v)
ppm (parts per million) = - 1 g/m3 - 1 g/1000L - 1 mg/L - 1 mg/kg
Mass/Volume % (m/v)
Volume/Volume % (v/v)
Mass/Mass % (m/m)
Medium in which solute is being dissolved (water, alcohol, etc.)
Substance being dissolved into a solvent (sugar, salt, etc.)
Cannot be filtered
- Can be separated into components - Looks the same throughout
P(total) = P1 + P2 + P3...
Formulas needed:
PV = nRT
R = 8.31 kPa*L/mol*K
P1/T1 = P2/T2
Absolute Zero: Theoretical Temperature where all matter would freeze. Absolute Zero is "-273 C" or "0 K"
Temperature recorded in 3 ways: Celsius (C) Fahrenheit (F) Kelvin (K) K = C + 273
The more kinetic energy the particles have, the higher the temperature
V1/T1 = V2/T2
Calculations always done in Kelvin
Shampoo bottle exploded on plane - Altitude increases, pressure decreases, making the volume increase
P1V1 = P2V2
Can be measured in: Kilopascals (kPa) Pascals (Pa) Atmospheres (atm) Millimeters of Mercury (mmHg) Torrs
(in closed systems) Multiple collisions increase pressure
If the forces are strong - solid If the forces are weak - Liquid or gas
For a molecule to be polar, it must be: - Containing a polar bond - Molecule does not have symmetry
An uneven distribution of charges due to unequal sharing of electrons
Ionic Bonds
Covalent Bonds
1. Hydrogen bonding 2. Dipole-dipole 3. London forces
Groups (4-8) = 8 - # of valence electrons
Groups (1-3) = # of group
related to # of valence electrons
Increases 🡳 and 🡰
Factors affecting size
Strength of attraction of valence electrons
Shielding effect - multiple energy levels
# of shells/energy levels
Half of distance from nucleus to valence
Tells us how 'efficient' a reaction was
Actual Yield: Actual amount of product formed
Theoretical Yield: Calculated or 'expected' amount of product formed
% Yield = Actual/Theoretical
To determine which reactant will be consumed first
Divide moles of each reactant by coefficient of reactant to find # of "cycles"
Reactant with more cycles is excess reactant with less is limiting
Given both reactants' masses
Use formulas: (n = m/M) and (n = N/Na)
Actual ratio for formula of a compound
Formula for a compound in the smallest whole number ratio
# of moles = # of entities/Avogadro's constant or n = N/Na
# of moles = mass(g)/Molar mass(g/mol) or n=m/M
**Avogadro's Constant**
- Burning of hydrocarbons - Complete combustion produces CO2 and H2O
Neutralization Reactions
Base + Acid 🡲 Salt + Water
Precipitation Reaction
Always has a solid and an aqueous product
- Element reacts with a compound and displaces the 2nd element to form a new compound and an element
- Reactant broken down into 2 or more products
- 2 different molecules/atoms combine to produce a compound