What is the volume of one mole of a gas at STP?

Identify the pH associated with acids and bases.

Give two ways that acids are different from bases that does not include their pH.

-____ ide (chloride, Cl - ) -____ ate (carbonate, C ) -____ ite (sulfite, S ) Anion Acidhydro____ ic acid____ ic acid____ ous acid HBr Hydrobromic acid H 2 CO 3 Carbonic acid H 2 SO 3 Sulfurous acid Add H+ BinaryPolyatomic Ions

ACIDSBASES H 2 CO 3 Calcium Hydroxide HNO 2 Ammonium hydroxide Sulfuric AcidKOH Sulfurous AcidLiOH Hydrobromic Acid Carbonic Acid Nitrous Acid H 2 SO 4 H 2 SO 3 HBr Ca(OH) 2 NH 4 OH Potassium hydroxide Lithium hydroxide

Arrhenius  gives off an H + and forms H 3 O + - increases the H+ when dissolved in water Bronsted  proton [H + ] donor (loses an H + ) HCl  H + + H 2 O  H + + Cl - H3O+H3O+

Monoprotic Acids ionizes into one H + ion (HCl) Diprotic Acids ionizes into two H + ions A.H 2 SO 4 + H 2 O  H 3 O + + HSO 4 - = 1 st B.HSO H 2 O  H 3 O + + SO 4 -2 = 2 nd Triprotic Acids - ionizes into three H + ions A.H 3 PO 4 + H 2 O  H 3 O + + H 2 PO 4 - = 1 st B.H 2 PO H 2 O  H 3 O + + HPO 4 -2 = 2 nd C.HPO H 2 O  H 3 O + + PO 4 -3 = 3 rd **Acids are strongest in their first ionization because it produces the most ions, then it gets weaker with each additional ionization H 2 SO 4 H 3 PO 4

Arrhenius  gives off an OH - Bronsted  proton [H + ] acceptor (gains an H + ) NaOH  Ca(OH) 2  Na + + OH - Ca +2 + OH - 2 **When a base completely dissociates in water it is called alkaline (synonym for basic)

1.pH < Electrolytes 3.Taste Sour 4.React with bases to form H 2 O + Salt 5.React with metals to form H 2(g) and salt Table J

1.pH > Electrolytes 3.Taste Bitter 4.React with acids to form H 2 O + Salt 5.Slippery, soapy feeling (turn you into Soap  Fight Club)

Above H 2 Below H 2 Any of those metals will react with an acid and produce Hydrogen gas Any of those metals will NOT react with an acid Will an acid react with a gold coin? Determine if a reaction will occur between zinc and hydrochloric acid. (write the reaction if it does)

- substances that dissolve and dissociate into solution, which allows them to conduct electricity Non-electrolyte – does not conduct electricity Weak-electrolyte – does not completely dissociate and conducts poorly Strong-electrolyte –completely dissociates and conducts well

If you were to place H 2 SO 4 onto a piece of copper, would it react to produce hydrogen gas? Explain your answer.

Chemicals which change colors when they are put into acids or bases. These indicators change colors in response the [H + ]. Table M

M A V A = M B V B -Perform titrations to determine an unknown volume or concentration of an acid/base -ENDPOINT = when indicator changes color -Moles of H + = Moles of OH - - Products are always water and salt M A = molarity of acid V A = volume of acid M B = molarity of base V B = volume of base

n A M A V A = n B M B V B If 20.0ml of a 0.50M HCl solution is needed to neutralize 65.0ml of a NaOH solution. What was the concentration of the base? M A = molarity of acid V A = volume of acid n A = # of H + ions M B = molarity of base V B = volume of base n B = # of OH - ions (1)(0.5M)(20.0ml) = (1)M B (65.0ml) M B = 0.154M

n A M A V A = n B M B V B 43.0ml of HCl was titrated with 32.0 ml of M Ca(OH) 2. What is the molarity of the hydrochloric acid solution? (1)M A (43.0ml)=(2)(0.100M)(32.0ml) M A = M

Setup for titrating an acid with a base

1.Close valve and put 50 ml of water in biuret 2.Open valve over sink and let 5 ml run out, flip biuret upside down and dump rest of water out of the top 3.Repeat 1 and 2 4.Put ~5 ml(45 ml mark on biuret) of acid(or base) in the appropriate biuret, swish liquid to coat entire inside, dump out the top 5.Repeat #4 but let the liquid drain through the valve 6.Fill biuret up with appropriate Acid (or Base) above the 0 mark, then drain in sink to drop level in biuret to 0.00 ml

Trial 1Trial 2Trial 3Avg Final Acid Volume Initial Acid Volume Final Base Volume Initial Base Volume Volume of Acid Used Volume of Base Used

Information related to an experiment is listed below: H 2 SO 4 + 2KOH  K 2 SO 4 + 2H 2 O Results Volume H 2 SO 4 used12.0 ml Concentration H 2 SO 4 ? Volume KOH used36.0 ml Concentration KOH0.16 M Based on the above results, what is the concentration of H 2 SO 4 ?

HCl + KOH  HOH + KCl acidbaseconj. acidconj. base Strong acids have weak conjugate bases Weak acids have strong conjugate bases HC 2 H 3 O 2 (aq) + H 2 O (l)  C 2 H 3 O 2 – (aq) + H 3 O + (aq) conjugate acid-base pairs acidbase conjugate acid conjugate base

Conjugate Pairs

What are electrolytes? Give two examples.

Depends on the concentration of dissociated ions Polarity More polar = stronger Bond Strength Stability of anion Stronger bond = weak because can’t dissociate More stable = stronger

Know these strong acids: HNO 3, H 2 SO 4, HCl, HBr, HI Strong Bases: NaOH, KOH

Conc & Strong Conc & WeakDilute & Strong Dilute & Weak

pH of Common Substances

pH = -log[H + ] -a way to measure the concentration of H + ions (H 3 O + ) in a solution -concentration of H + = [H + ] If [H 3 O + ] = 1 x 10 -4, then pH =4 pOH = -log[OH - ]

At 25ºC, pH + pOH = 14 So if a solution is basic  If [OH] = M, what is the pH? [H + ]x[OH - ] = Solution: the OH = 8, so the pH must be 14 – 8 So the pH = 6 So if a solution is basic 

from concentrations You need the concentration of [H + ],[H 3 O + ], or [OH - ] If the concentration of [H + ] is 1 x 10 -3, then pH=3 If HNO 3 is 6.5 x M, what is the pH? pH = -log[6.5 x ] pH=11.19 If H 2 SO 4 is 6.5 x M, what is the pH? [H 3 O + ] = 2 x 6.5 x pH = -log[1.3 x ] pH=10.89 pH = -log[H + ]

What is the pH of a M NaOH solution? pH=11 If the concentration of magnesium hydroxide is 2.5 x M, what is the pH? [OH-]= M Mg(OH) 2 = 1.00 x M pOH= 3 pH=12.7 from concentrations

Rearange, so [H 3 O + ] = 10 -pH Determine the [H 3 O + ] in an aqueous solution with a pH of 4.0 Mg(OH) 2 pH=12.7 from pH pH = -log[H + ]

Because it is a logarithmic scale, each one unit change in pH really represents a 10 fold change in [H + ] So going from a pH of 6 to 7 really represents a 10 fold decrease in the number of [H + ] What is the difference in [H + ] in a pool that has a pH of 6, but in reality you want it to have a pH of 7?

What is the pH of a molar HCl solution? If the pH of your pool is 6, what is the concentration of hydronium ions in solution? As the pH of a solution is changed from 3 to 6, how does the concentration of hydronium ions change? An aqueous solution that a [H + ] of 1.0 x mole per liter has a pH of?

Solution A has a pH of 1 and solution Z has a pH of 5. How many times greater is the hydronium ion concentration in solution A?

KwKw KaKa KbKb Ionization Constant for water Acid Dissociation Constant Base Dissociation Constant Written like K eq with products over reactants and coefficients as exponents K w = [H 3 O + ] ∙[OH - ] K w = 1 x When neutral, both ions are = 1 x Same as above HA ↔ H 3 O + + A - Large K a = high tendency for H to dissociate = stronger acid Small K a = low tendency for H to dissociate = weaker acid

-A compound that does not allow the pH to change even if an acid or base is added to the system -They have the ability to absorb/release H+ which will keep the pH relatively constant -Good buffers are amphiprotic substances -Amphiprotic – something that can act as an acid and a base

-Blood pH -Adirondack lakes Brooktrout Lake "Treat the earth well: it was not given to you by your parents, it was loaned to you by your children. We do not inherit the Earth from our Ancestors, we borrow it from our Children."

Effects of Acid Rain on Marble (marble is calcium carbonate) George Washington: BEFORE acid rain George Washington: AFTER acid rain

The pH of a lake is 8.0. Over a 10 year period, the pH of the water becomes 1000x more acidic. 1.Name an ion that has increased in the water over the 10 years? 2.What is the pH now? 3.If you were to use bromothymol blue to test the pH, what color would it be at the end? [Use R.T.]

Dump all acid/base from biurets and beakers Fill Buiret with warm water and run through valve Repeat 1 more time Place biuret in stand upside down and with valve open

1. H 2 O + H 2 O  H 3 O + + OH - 2. H 2 SO 4 + OH -  HSO H 2 O 3. HSO H 2 O  SO H 3 O + 4. OH - + H 3 O +  H 2 O + H 2 O 5. NH 3 + H 2 O  NH OH -

ACIDBASEEQUATION 1 H 2 SO 4 HSO H 3 PO 4 3 F-F- 4 NO H 2 PO H2OH2O 7 SO HPO NH H2OH2O H 2 PO 4 - HF HNO 3 HPO 4 -2 OH - HSO 4 - PO 4 -3 NH 3 H3O+H3O+ H 3 PO 4 ↔ H + + H 2 PO 4 - HF ↔ H + + F - HNO 3 ↔ H + + NO 3 - H 2 PO 4 - ↔ H + + HPO 4 -2 H 2 O ↔ H + + OH - HSO 4 - ↔ H + + SO 4 -2 HPO 4 -2 ↔ H + + PO 4 -3 NH 4 + ↔ H + + NH 3 H 3 O + ↔ H + + H 2 O

PART C 26.A, C, D 27.D 28.Presence of H + ions 29.C 30.C – skip this one!!!!! 31.(10.01mL)(0.100M)= MB(5.01ml) M Colorless to pink M M 36. Reduces error, increases reliability 37. Ca(OH) 2 + H 2 SO 4  CaSO 4 + 2H 2 O 38. pH= M 40. HCl – 9.50 ml NaOH – 3.80 ml mL 42. Methyl orange, brom blue, thymol blue 43. Between 4.4 and Yellow

PART A PART B

In a lab there were three flasks, one filled with methanol, another had NaOH, and the third HCl. ID these liquids. Test Test Results Bottle ABottle BBottle C Methyl orange Yellow Bromthymol Blue BlueGreenYellow Conductivity ConductorNonconductorconductor Reaction with Mg No Rxn Rxn 1.A student concluded that bottle C contained HCl. Identify one way that supports this finding. 2.Explain in terms of pH, why methyl orange was the same for all three liquids.

What is the volume of 1.00 mole of any gas at STP? Hint: Lab