Writing Reactions --for unbalanced students

A few things to recall-- Synthesis Decomposition Single replacement Double replacement Other redox

A+B AB

AB A+B

A+BC AC+B Or D+BC C+BD

AB+CD AD+BC

AB+CD a whole bunch of other things.

A few things to recall-- Metallic oxides and water make hydroxides M 2 O+H 2 O 2MOH MO+H 2 O M(OH) 2 2M 2 O 3 +3H 2 O 2M(OH) 3

A few things to recall-- Nonmetallic oxides and water make acids YO + H 2 O H 2 YO 2 YO 2 + H 2 O H 2 YO 3 YO 3 + H 2 O H 2 YO 4 2Y 2 O 5 + H 2 O 2HYO 3

A few things to recall-- In a single replacement reactionthe more reactive element replaces the less reactive X +MY Y +MX means X is a more reactive nonmetal than Y A + BC B + AC means A is a more reactive metal than B

A few things to recall-- In a double replacement reaction, you need a molecule or a precipitate formed AB +CD AD + BC if AD and BC are both soluble salts

A few things to recall-- Carbonates decompose with heat or acid

A few things to recall-- In a redox reaction, hydrogen ions and water can be reactants or products.

A few things to recall-- In a redox reaction, you have to balance the charge as well

A few things to recall-- Net ionic equations show dissociated ions, spectators are omitted AB +CD AD + BC, if AD is soluble, Write: B - +C + BC

Predict the products AKA: Descriptive chemistry You are given to reactants. What products are formed? Go!

Predict the products Old Rules –8 sets, you choose 5 –Dont balance –Use a net ionic equation New rules– –Three sets, do all of them –Balance –Use a net ionic equation –Answer a question

Predict the products We will practice old rules first.

What do you see? 1. A piece of solid bismuth is heated strongly in oxygen. 2. A strip or copper metal is added to a concentrated solution of sulfuric acid. 3. Solutions of zinc sulfate and sodium phosphate are mixed. 4. Solutions of silver nitrate and lithium bromide are mixed. 5. A stream of chlorine gas is passed through a solution of cold dilute sodium hydroxide. 6. Excess hydrochloric acid solution is added to a solution of potassium sulfite. 7. A solution of tin (II) chloride is added to an acidified solution of potassium permanganate 8. A solution of ammonium thiocyanate is added to a solution of iron (III) chloride.

What do you see? 1. A piece of solid bismuth is heated strongly in oxygen. 2. A strip or copper metal is added to a concentrated solution of sulfuric acid. 3. Solutions of zinc sulfate and sodium phosphate are mixed. 4. Solutions of silver nitrate and lithium bromide are mixed. 5. A stream of chlorine gas is passed through a solution of cold dilute sodium hydroxide. 6. Excess hydrochloric acid solution is added to a solution of potassium sulfite. 7. A solution of tin (II) chloride is added to an acidified solution of potassium permanganate 8. A solution of ammonium thiocyanate is added to a solution of iron (III) chloride. It will burn

What do you see? 1. A piece of solid bismuth is heated strongly in oxygen. 2. A strip or copper metal is added to a concentrated solution of sulfuric acid. 3. Solutions of zinc sulfate and sodium phosphate are mixed. 4. Solutions of silver nitrate and lithium bromide are mixed. 5. A stream of chlorine gas is passed through a solution of cold dilute sodium hydroxide. 6. Excess hydrochloric acid solution is added to a solution of potassium sulfite. 7. A solution of tin (II) chloride is added to an acidified solution of potassium permanganate 8. A solution of ammonium thiocyanate is added to a solution of iron (III) chloride. Can only be oxidized

What do you see? 1. A piece of solid bismuth is heated strongly in oxygen. 2. A strip or copper metal is added to a concentrated solution of sulfuric acid. 3. Solutions of zinc sulfate and sodium phosphate are mixed. 4. Solutions of silver nitrate and lithium bromide are mixed. 5. A stream of chlorine gas is passed through a solution of cold dilute sodium hydroxide. 6. Excess hydrochloric acid solution is added to a solution of potassium sulfite. 7. A solution of tin (II) chloride is added to an acidified solution of potassium permanganate 8. A solution of ammonium thiocyanate is added to a solution of iron (III) chloride. Look for a precipitate

What do you see? 1. A piece of solid bismuth is heated strongly in oxygen. 2. A strip or copper metal is added to a concentrated solution of sulfuric acid. 3. Solutions of zinc sulfate and sodium phosphate are mixed. 4. Solutions of silver nitrate and lithium bromide are mixed. 5. A stream of chlorine gas is passed through a solution of cold dilute sodium hydroxide. 6. Excess hydrochloric acid solution is added to a solution of potassium sulfite. 7. A solution of tin (II) chloride is added to an acidified solution of potassium permanganate 8. A solution of ammonium thiocyanate is added to a solution of iron (III) chloride. Look for a precipitate

What do you see? 1. A piece of solid bismuth is heated strongly in oxygen. 2. A strip or copper metal is added to a concentrated solution of sulfuric acid. 3. Solutions of zinc sulfate and sodium phosphate are mixed. 4. Solutions of silver nitrate and lithium bromide are mixed. 5. A stream of chlorine gas is passed through a solution of cold dilute sodium hydroxide. 6. Excess hydrochloric acid solution is added to a solution of potassium sulfite. 7. A solution of tin (II) chloride is added to an acidified solution of potassium permanganate 8. A solution of ammonium thiocyanate is added to a solution of iron (III) chloride. Can be reduced

What do you see? 1. A piece of solid bismuth is heated strongly in oxygen. 2. A strip or copper metal is added to a concentrated solution of sulfuric acid. 3. Solutions of zinc sulfate and sodium phosphate are mixed. 4. Solutions of silver nitrate and lithium bromide are mixed. 5. A stream of chlorine gas is passed through a solution of cold dilute sodium hydroxide. 6. Excess hydrochloric acid solution is added to a solution of potassium sulfite. 7. A solution of tin (II) chloride is added to an acidified solution of potassium permanganate 8. A solution of ammonium thiocyanate is added to a solution of iron (III) chloride. Weak base

What do you see? 1. A piece of solid bismuth is heated strongly in oxygen. 2. A strip or copper metal is added to a concentrated solution of sulfuric acid. 3. Solutions of zinc sulfate and sodium phosphate are mixed. 4. Solutions of silver nitrate and lithium bromide are mixed. 5. A stream of chlorine gas is passed through a solution of cold dilute sodium hydroxide. 6. Excess hydrochloric acid solution is added to a solution of potassium sulfite. 7. A solution of tin (II) chloride is added to an acidified solution of potassium permanganate 8. A solution of ammonium thiocyanate is added to a solution of iron (III) chloride. Can be reduced

What do you see? 1. A piece of solid bismuth is heated strongly in oxygen. 2. A strip or copper metal is added to a concentrated solution of sulfuric acid. 3. Solutions of zinc sulfate and sodium phosphate are mixed. 4. Solutions of silver nitrate and lithium bromide are mixed. 5. A stream of chlorine gas is passed through a solution of cold dilute sodium hydroxide. 6. Excess hydrochloric acid solution is added to a solution of potassium sulfite. 7. A solution of tin (II) chloride is added to an acidified solution of potassium permanganate 8. A solution of ammonium thiocyanate is added to a solution of iron (III) chloride. Its complex

Arrhenius acids and bases Substances that ionize in water to form H + ions are acids. Substances that ionize in water to form OH - ions are bases.

Br Ø nsted-Lowry Definition Substances that donate a proton (H + ion) in a reaction are acids. Substances that accept a proton (H + ion) are bases.

Lewis Definition Substances that accept an electron pair in a reaction are acids. Substances that donate an electron pair are bases.

Conjugates After an acid has donated a proton, the rest of the species is the conjugate base. HA A - + H + After a base has accepted a proton, the resulting species is the conjugate acid. B - + H + HB

Please recall: Strong acids and bases dissociate completely in a water environment. Weak acids and bases do not. Strong acids= nitric, hydrochloric, sulfuric, hydrobromic, hydroiodic, perchloric Strong bases-Group 1 & 2 hydroxides (group 2s might not dissolve well)

We did not use: (but you still have to know) These ions:Precipitate like: MnO 4 -, O 2 -2,CN -,ClO 4 - like NO 3 - F - like Cl - Mn +2,Fe +2 like Fe +3 C 2 O 4 -2 like CO 3 -2 S -2 like OH - Hg 2 +2 like Ag + (oxides do not exist in a water solution!)

H + + OH - H 2 O Just remember– One H + neutralizes one OH - Its true for strong and weak acids and bases.

H + + OH - H 2 O Just remember– One H + neutralizes one OH - Its true for strong and weak acids and bases. M 1 V 1 =M 2 V 2 Moles of H + Moles of OH -

A titration If ml of a.115M NaOH solution neutralizes ml of HCl solution, what is the concentration of the original acid?

Another titration If ml of a.115M H 2 SO 4 solution neutralizes ml of NaOH solution, what is the concentration of the base?

Another titration If ml of a.115M H 2 SO 4 solution neutralizes ml of NaOH solution, what is the concentration of the base? Did you catch that?

Dilution Add more solvent to a solution, the concentration decreases. M 1 V 1 =M 2 V 2 Moles of solute

A dilution If 150 ml of a.30 M NaOH solution is diluted to 250 ml, what is the new concentration of the base?

Another dilution What volume of solvent must be added to 100. ml of 1.5 M NaCl to make a solution that is.30 M [Cl - ]?

Another dilution What volume of solvent must be added to 100. ml of 1.5 M NaCl to make a solution that is.30 M [Cl - ]? Did you catch that? Not to what new volume must it be diluted?

Life is pain, Your Highness. Wesley, from the Princess Bride by William Goldman

What is [Cl - ]? 150 ml of.2 M NaCl, 250 ml of.4 M AlCl ml of.35 M MgCl 2 and 100 ml H are mixed (assume volumes are additive, that is, V final =700 ml)

What will happen…...if you add, to 1.0 L H 2 O at room temperature, the following substances, in order: 5 g Na(s) 5 g Mg(s) 5 g NaCl(s) 5 g Zn(C 2 H 3 O 2 ) 2 (s) 5 g HCl(g) 5 g H 3 PO 4 (l)