Chemistry Exam Review

This set of flashcards covers key vocabulary and concepts related to chemistry, specifically focusing on solubility, gas laws, molarity, and stoichiometry.

Solubility Rules

Guidelines to predict if an ionic compound dissolves in water.

• Soluble Ions: Alkali metals (Li^+, Na^+, K^+, Rb^+, Cs^+), Ammonium (NH4^+), Nitrate (NO3^-), Acetate (CH3COO^-), Perchlorate (ClO4^-).

• Generally Soluble (with exceptions):

  • Halides (Cl^-, Br^-, I^-): Insoluble with Ag^+, Pb^{2+}, Hg_2^{2+}.

  • Sulfates (SO4^{2-}): Insoluble with Ba^{2+}, Pb^{2+}, Hg2^{2+}, Ca^{2+}, Sr^{2+}.

• Generally Insoluble (with exceptions):

  • Hydroxides (OH^-$), Carbonates (CO3^{2-}$), Phosphates (PO4^{3-}$), Sulfides (S^{2-}$): Soluble with Alkali metals and Ammonium (NH_4^+).

Things to Remember:

• KISS: Key Ions Six Soluble: K^+, Na^+, NH4^+, NO3^-, CH3COO^-, ClO4^-.

• Halides exceptions: "Heavy Plumbers Always Get Handcuffed" (Hg_2^{2+}, Pb^{2+}, Ag^+).

Balancing Chemical Equations

Adjusting coefficients to ensure the number of atoms for each element is equal on both sides of a chemical reaction, following the Law of Conservation of Mass.

Things to Remember:

• Law of Conservation of Mass: Atoms are neither created nor destroyed. What goes in must come out!
• "Celebrate Hydrogen Oxygen, then Rest" (CHOR) for order of balancing.

STP (Standard Temperature and Pressure)

Standard conditions: 0^o C (273.15 K) and 1 atm (101.325 kPa). Under these, 1 mole of any ideal gas occupies 22.4 Liters.

Things to Remember:

• "STP is 0 degrees and 1 atmosphere, yielding 22.4 liters for 1 mole."

Gay Lussac's Law

For a fixed gas at constant volume, pressure is directly proportional to its absolute temperature. Thus, as temperature increases, pressure increases. Formula: \frac{P1}{T1} = \frac{P2}{T2}.

Things to Remember:

• "Gay Lussac’s is Pressure-Temperature (PT) Directly proportional." Always use Kelvin!

Molarity

Concentration of a solution, defined as moles of solute per liter of solution. Formula: M = \frac{mol}{L}. Units: M (moles/Liter).

Things to Remember:

• "Moles over Liters" (M = mol/L).

Dilution

Reducing a solution's concentration by adding more solvent, keeping the total moles of solute constant. Formula: M1V1 = M2V2.

Things to Remember:

• "Moles before dilution = Moles after dilution."

Limiting Reactant

The reactant completely used up first in a chemical reaction, which limits the amount of product formed.

Things to Remember:

• "The Limiting Reactant Limits Results."
• Sandwich analogy: If you have less cheese than bread, cheese is the limiting reactant for sandwiches.