Unit 7 Solutions, Acids & Bases Solution mixture + solvent - substance present in the amount solute - in the solvent solvent molecules solute particles ionic substances (separate) based on! Liquid Mixtures miscible two liquids that and form a immiscible two liquids that form a e.g. and solvent is still the in the amount Solubility ability of a to be in a the amount that can be Factors that affect solubility as increases, solubility NOT true for a (as, ) : dissolves solvents dissolve solutes solvents dissolve solutes
Solubility Curve solution the amount of has been dissolved in the solvent the solvent is and cannot any excess will out solution the solvent has the ability for solute to not solution a VERY condition more solvent is added by the, then very slowly allowing the to
Predict the type of solution 50 g of NaNO 3 in 100 g of water at 40 C 75 g of KNO 3 in 100 g of water at 55 C 50 g of NaCl in 100 g of water at 60 C 100 g of NaNO 3 in 200 g of water at 80 C Concentration a measure of the amount of that is dissolved in the Molarity vs. solubility the possible amount of solute that could be M n V dissolved n = V = ( ) Molarity as a Formula What is the molarity of a solution when 30.0 g of sodium hydroxide are dissolved in 500.0 ml of water?
Molarity as a Conversion Factor How much sodium chloride is required to prepare 250.0 ml of a 0.100 M solution? How much potassium nitrate is required to prepare 100.0 ml of a 0.0500 M solution? Vocabulary to be careful about a substance that dissociates when dissolved in a solvent a substance that dissociates only when dissolved in a solvent a amount of solute (close to or at saturation) a amount of solute (very unsaturated) Dilution M 1 V 1 = M 2 V 2 M 1 = V 1 = M 2 = V 2 =
What volume of 2.00 M HCl is needed to prepare 100.0 ml of a 0.400 M HCl solution? Describe how to prepare 250.0 ml of 0.100 M H 2 SO 4 from a 12.0 M H 2 SO 4 solution. Naming Acids Anion Ending Rule - hydro ic acid - ous acid - ic acid Practice naming acids HCl HClO 2 HClO 3 Acid that must be memorized HCl hydrochloric acid (strong) HNO 3 nitric acid (strong) H 2 SO 4 sulfuric acid (strong) H 3 PO 4 phosphoric acid (weak) ** NH 3 ammonia (weak base)
Strong Acids Seven strong acids HCl, HBr, HI, HNO 3, H 2 SO 4, HClO 3, and HClO 4. Strong because they completely in water Strong Bases metal heavier metal (Ca 2+, Sr 2+, and Ba 2+ ). Arrhenius Acid Reacts with to increase the of, H 3 O + HCl + H 2 O Cl + H 3 O + H 2 SO 4 + 2 H 2 O SO 2 4 + 2 H 3 O + Arrhenius Base Reacts with to increase the of the, OH NaOH Na + + OH NH 3 + H 2 O NH 4 + + OH Brønsted-Lowry Acid can a (H + ) HCl H + + Cl can donate only proton can donate protons (e.g. H 2 SO 4 ) can donate protons (e.g. H 3 PO 4 )
Brønsted-Lowry Base can a NH 3 + H 2 O NH 4 + + OH Amphiprotic (Amphoteric) can act as an or a HSO 4 + H + H 2 SO 4 HSO 4 H + 2 + SO 4 Conjugate Acids & Bases the created from the original the created from the original Identify the Conjugate Acid Base Pairs NH 3 + H 2 O NH 4 + + OH H 2 SO 4 + H 2 O HSO 4 + H 3 O + Equilibrium a dynamic where the amount of and do not for each set of that form, a set of will undergo the reaction to form does occur in reactions noted in the reaction using
Autoionization of Water Water is In pure water, a few molecules act as and a few act as. H 2 O + H 2 O H 3 O + + OH Water at Equilibrium At [ ] = [ ] K w = [H 3 O + ] [OH ] = 1.0 x 10 14 [x] = concentration of x (molarity) ph a measure of / ph scale 0 7 7 (pure ) 7 14
Finding ph ph = log [H 3 O + ] [H 3 O + ] = 10 -ph What is the ph of a 0.010 M HCl solution? What is the ph of a 0.010 M H 2 SO 4 solution? poh scale 0 7 7 7 14 ph + poh = 14 poh = log [OH ]
Summary of ph formulas ph + poh = 14 ph = log [H 3 O + ] poh = log [OH ] K w = [H 3 O + ] [OH 14 [H 3 O + ] = 10 -ph [OH ] = 10 -poh What is the ph of a 0.650 M NaOH solution? What is the concentration of KOH solution with a ph of 9.4? What is the concentration of a HBr solution with a ph of 3.5? What is the [OH ] of the previous HBr solution?
What is the ph of a 0.350 M calcium hydroxide solution? Neutralization Reactions + + sodium hydroxide + hydrochloric acid sulfuric acid + potassium hydroxide How Do We Measure ph? (most accurate) Titration a experimental method of determining the of a solution use your! http://www.youtube.com/watch?v=ig9ppml3ede&nr=1
A 25.0 ml sample of sulfuric acid is completely neutralized by 18.0 ml of 1.0 M NaOH. What is the concentration of sulfuric acid? What is the concentration of phosphoric acid if 15.0 ml of the solution is completely neutralized by 38.5 ml of 0.150 M NaOH? What volume of 0.45 M hydrochloric acid must be added to 25.0 ml of 1.00 M potassium hydroxide to reach the end point?