Acid/Base Review
List the properties of Acids Sour, H3O+ ions, strong acids conduct, react with metals to form H2 gas, neutralize bases to form salt + water. Acids Ionize with water to form H3O+, litmus red
List the properties of bases Bitter, slippery, OH- ions, strong bases conduct, , neutralize acids to form salt + water. Strong bases dissociate (water on arrow), litmus blue
List the 6 strong acids HBr HI HCl HNO3 H2SO4 HClO4 Remember these acids ionize completely in water creating a strong electrolyte!
Explain the difference between an oxyacid and a binary acid and give an example of each Oxyacid has oxygen in the compound H2SO4 Binary acid means that there are two compounds present HCl
List common acids that we have talked about Phosphoric Acid-found in soda/used to make fertilizer HCl-found in the stomach Acetic Acid-vinegar
Give two examples of weak acids and one example of a weak base H2S-Hydrosulfuric Acid HCH3COO-acetic acid NH3 – ammonia (weak base)
List the strong bases Anything in column 1 & 2 bonded with an OH-
Explain the Arrhenius Acid Definition Acids produce H+ in solution Acid – produces H+ in water HCl + H2O H3O+ + Cl- H2SO4 + H2O 2H3O+ + SO42- Remember H+ can also mean H3O+ (Hydronium Ion)
Explain the Arrhenius Base Definition Base – produces OH- in water NaOH Na+ + OH- NH3 + H2O NH4+ + OH-
Explain the Bronsted-Lowrey Definition of Acids/Bases Acids are H+ donors, bases are proton (H+ ) acceptors. HCl + H2O Cl + H3O+ acid base Bronsted-Lowry is a way to study proton transfer!!
Explain conjugate Acid/Base Conjugate Acid – formed when BL base gains a proton Conjugate Base – formed when BL acid looses a proton HCl + NH3 NH4+ + Cl- a b ca cb H2SO4 + 2H2O 2 H3O+ + SO42- a b ca cb
If I have a strong acid what is the strength of the conjugate base? The stronger the acid, the weaker its conjugate base; the stronger the base, the weaker its conjugate acid
Study your conjugate acid/base worksheet as there are a few questions on recognizing a/cb and b/ca pairs
What is an amphoteric substance and give an example Water: can react as either an acid or base HCl + Water H3O + + Cl - proton acceptor(water) Water + NH3 NH4 + + OH - Water(proton donor)
Complete the following Reactions 3KOH + H3PO4 → K3PO4 + 3 H2O Mg(OH)2 + 2 HCl → 2H2O + MgCl2
Are strong acids/bases strong or weak electrolytes? Strong because they will completely ionize or dissociate creating many ions……. Weak acids/bases do not ionize completely thus there are fewer electrons, thus they are not very strong electrolytes
How many moles of Nitric acid are in 500 ml of a 10 M HNO3 solution?
What does pH measure? pH – related to the concentration of H3O + ions in solutions. The more H3O+ ions, the lower the pH.
Given the H3O+ concentration find the pH / pOH…A/N/B [H3O+]=7.3x10-13 pH=12.13 pOH=1.86 Basic [H3O+]=5x10-2 pH=1.3 pOH=12.2 Acidic
Given the pH find the Hydronium or hydroxide ion concentration [H3O+]= 7.9x10-4 pH= 10.5 [H3O+]=3.2x10-11
Draw a strong acid/strong base titration curve
Draw a weak base strong acid titration curve
Summary of titration curves
During a titration curve why do we have to titrate so slowly when we get close to the equivalence point/end point? When the hydronium ions and hydroxide ions are nearly equal (the equivalence point) the curve of graph is very steep and thus happens very quickly.
Explain the End Point When the indicator changes color which should be close to the equivalence point if chosen correctly. Ex. Strong acid/strong base should be litmus Ex. Strong base/weak acid should be phenolphthalein
What is the pH of a .036M LiOH solution First find the pOH by finding the normality Remember normality = molarity x equivalence Then you take the –log (normality concentration) -log (.036)=1.44 but that equals the pOH Then you take 14-1.44=12.56 which gives you the pH pH=12.56
To neutralize 20 ml of aqueous sulfuric acid, you use 32. 5 ml of a 0 To neutralize 20 ml of aqueous sulfuric acid, you use 32.5 ml of a 0.2 M NaOH solution. Calculate the Molarity Molarity of H2SO4 =0.16
What volume of 0.5 M sulfuric acid is needed to react completely with 10 ml of 2.0 M LiOH H2SO4 + 2LiOH → Li2SO4 + 2H2O .02L
Molarity = HCH3COO=0.367 Normality = M x eq = 0.367 x 1 = 0.367 A 20 ml sample of 0.55 M KOH solution required 30 ml of aqueous acetic acid solution in a titration experiment. Calculate M & N &pH of the acid. Molarity = HCH3COO=0.367 Normality = M x eq = 0.367 x 1 = 0.367 pH= -log [N]= -log(0.367) = .435
If you start with a pH of 1 and add water what should you expect to have happen to the pH? You should expect it to neutralize pH of 1 = .1M When you add water you dilute it so the next step would be .01M. The pH would be 2. .001M = pH 3 etc. What would a graph look like?
You have a 4 M solution of NaOH. You need to make up 2000 ml of a 1 You have a 4 M solution of NaOH. You need to make up 2000 ml of a 1.5 M solution. How many mls of the 4 M solution do you need? How much water would you need? V1 x M1 = V2 x M2 V1 x 4M = 2000 x 1.5 V1=750ml
What is the salt produced when KOH is used to neutralize sulfuric acid? K2SO4