University:
High School
Course:
High School Chemistry
Academic year:

2020
Views:

450

Pages:

8
Author:

corsarsdh

***Give two definitions for solubility: Maximum amount of Solute that can be dissolved in a given amount of solvent at a specific temperature. This is quantitative - use Table G The ability of a substance (Solute) to dissolve in a solution. This is qualitative - use Table F Using Table G Determine if the following are saturated, unsaturated, or supersaturated: a. 60 g KCl at 70°C SAT b. 90 g KNO₃ at 60°C UNSAT c. 110 g NaNO₃ at 45°C SAT d. 10 g KClO₃ at 10°C SUPER e. 60 g NH₄Cl at 70°C UNSAT Determine the number of grams of solute required to make a saturated solution in 100 grams of water: a. NaNO₃ at 30°C 95g b. KClO₃ at 70°C 31g c. KNO₃ at 45°C 75g d. KCl at 40°C 39g e. NaCl at 90°C 40g Most substances on Table G show increased solubility as temperature increases. What are the exceptions? HCl, NH₃, SO₂ a. What type of substances are they? gases Slope down. The solubilities of substances whose curves show greater (steeper) slopes are more (more or less) affected by temperature changes than those with more gradual slopes. a. Which salt's solubility is least affected by changes in temperature? NaCl → flat line Using Table F State whether the following compounds are soluble or insoluble in water. Also, if they are soluble, show the dissociation of ions. potassium chloride Soluble K⁺ + Cl⁻ calcium chromate Soluble Ca²⁺ + CrO₄²⁻ NaNO₃ Soluble Na⁺ + NO₃⁻ aluminum phosphate Insoluble No Ions Ba(OH)₂ Soluble Ba²⁺ + 2OH⁻ AgCl Insoluble No Ions lead (II) sulfate Insoluble No Ions LiClO₃ Soluble Li⁺ + ClO₃⁻ ammonium carbonate Soluble NH₄⁺ + NH₄⁺ + CO₃²⁻ MgS Insoluble No Ions Using Table F (Solubility Table), indicate which product is the precipitate (insoluble) and which product is aqueous (soluble). CaCl₂(aq) + Na₂CO₃(aq) → CaCO₃(s) + 2NaCl(aq) Precip Sol CaCl₂(aq) + Na₂SO₄(aq) → CaSO₄(s) + 2NaCl(aq) Precip Sol K₂CrO₄(aq) + CuCl₂(aq) → 2KCl(aq) + CuCrO₄(s) Sol Precip BaCl₂(aq) + K₂CO₃(aq) → BaCO₃(s) + 2KCl(aq) Precip Sol 3Pb(NO₃)₂ + 2Na₃PO₄ → Pb₃(PO₄)₂(s) + 6NaNO₃(aq) Precip Sol The following solutions are mixed together. Predict whether a precipitate will form and indicated its name. Example: potassium chromate and copper chloride Potassium Chromate: K₂CrO₄ → 2K⁺ + CrO₄²⁻ Copper Chloride: CuCl₂ → Cu²⁺ + 2Cl⁻ → 2KCl(aq) + CuCrO₄(s) Sol Insol Precip Go to Table F "Solubility Guidelines" and look up BOTH compounds. If the compound is soluble, then write (aq) which means aqueous next to its formula. This means the ions remain as free ions in solution. If the compound is insoluble according to Table F, write (s) after the compound. This means the compound is a solid precipitate and the ions have bonded to form a compound. Now try these!! silver nitrate + potassium chloride → AgCl(s) + KNO₃(aq) AgNO₃ → Ag⁺ + NO₃⁻ KCl → K⁺ + Cl⁻ Insol Sol sodium sulfate + barium acetate → Na₂SO₄(aq) + BaSO₄(s) Na₂SO₄ → 2Na⁺ + SO₄²⁻ Ba(C₂H₃O₂)₂ → Ba²⁺ + 2C₂H₃O₂⁻ Sol Insol sodium carbonate + calcium chloride → NaCl(aq) + CaCO₃(s) Na₂CO₃ → 2Na⁺ + CO₃²⁻ CaCl₂ → Ca²⁺ + 2Cl⁻ Sol Insol