Solutions and Titration Chemistry

• Chemistry topics covered include solutions, acids and bases, redox reactions, gas laws, and stoichiometry.

Solutions and Their Components

• A solution is a mixture where one substance dissolves into another.
• The solvent is the substance that does the dissolving.
• The solute is the substance being dissolved.
• Molarity (M) measures solution concentration as moles of solute per liter of solution.
• Molarity formula: M = (moles of solute) / (liters of solution)
• Dilution is adding water to a concentrated solution.
• Dilution formula: M1V1 = M2V2, where M and V are molarity and volume.

Titrations and Solution Stoichiometry

• Titration determines the concentration of an unknown solution.
• Titration involves reacting the unknown solution with a solution of known concentration.
• An indicator is used to signal when the reaction is complete via color change.
• At the equivalence point, the amount of acid equals the amount of base.
• The dilution equation M1V1 = M2V2 is used.
• Stoichiometry problems with solutions involve converting givens into moles using molarity.
• Use the balanced equation to find the mole ratio between reactants and products.
• Convert moles back into the needed units like grams or liters.

Electrolytes, Acids, and Bases

• Electrolytes are substances that conduct electricity in water by forming ions.
• Strong electrolytes completely break apart into ions (e.g., NaCl, HCl).
• Weak electrolytes partially break apart (e.g., acetic acid CH3COOH).
• Non-electrolytes do not break apart at all (e.g., sugar, ethanol).
• Acids donate H+ ions, while bases donate OH- ions.
• Strong acids completely ionize (e.g., HCl, H2SO4).
• Weak acids partially ionize (e.g., HF, CH3COOH).
• Strong bases completely ionize (e.g., NaOH, KOH).
• Weak bases only partially ionize (e.g., NH3 ammonia).

Redox Reactions and Oxidation Numbers

• Redox reactions involve the transfer of electrons between substances.
• Oxidation is losing electrons, increasing the oxidation number.
• Reduction is gaining electrons, decreasing the oxidation number.
• OIL RIG: Oxidation Is Loss, Reduction Is Gain.
• Elements by themselves have an oxidation number of 0 (e.g., O2, N2, Zn).
• Group 1 metals always have an oxidation number of +1; Group 2 metals always +2.
• Oxygen usually has an oxidation number of -2, except in peroxides.
• Hydrogen is +1 with nonmetals and -1 with metals.

Balancing Chemical Equations

• Following the Law of Conservation of Mass is important in balancing equations.
• The number of atoms on both sides of the equation must be equal.
• Combustion reactions involve hydrocarbons reacting with oxygen to form CO2 and H2O (e.g., CH4 + O2 → CO2 + H2O).
• Balance carbon first, then hydrogen, then oxygen.

Stoichiometry, Limiting Reactants, and Percent Yield

• Stoichiometry problems relate reactants and products in a balanced chemical equation.
• Limiting reactant problems determine which reactant runs out first, limiting product formation.
• Percent yield compares actual product yield to theoretical yield, shown as: Percent Yield = (Actual Yield / Theoretical Yield) × 100.

Gas Laws and the Ideal Gas Equation

• Gas laws describe the relationships between pressure, volume, temperature, and moles of gas.
• Boyle's Law: Pressure and volume are inversely proportional (P1V1 = P2V2).
• Charles' Law: Volume and temperature are directly proportional (V1/T1 = V2/T2).
• Gay-Lussac's Law: Pressure and temperature are directly proportional (P1/T1 = P2/T2).
• Combined Gas Law: Combines Boyle's, Charles', and Gay-Lussac's Laws (P1V1/T1 = P2V2/T2).
• Ideal Gas Law: PV = nRT, where P = pressure, V = volume, n = moles of gas, R = gas constant (0.0821 L-atm/mol-K), T = temperature (Kelvin).
• When collecting gas over water, subtract water's vapor pressure from the total pressure.

Learn chemistry: solutions, titrations, and stoichiometry. Understand molarity, dilution, and titrations. Explore indicators and equivalence points.