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Friday, Sept. 6 th : “A” Day Monday, Sept. 9 th : “B” Day Agenda. Homework Questions/Collect Finish Sec. 8.3: “Classifying Chemical Reactions” Single and double displacement reactions, activity series Homework: Sec. 8.3 review, pg. 285: 5-7, 8a,d,e, 9a-d, 10c,d, 11, 13, 14
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Friday, Sept. 6th: “A” DayMonday, Sept. 9th: “B” DayAgenda • Homework Questions/Collect • Finish Sec. 8.3: “Classifying Chemical Reactions” • Single and double displacement reactions, activity series • Homework: • Sec. 8.3 review, pg. 285: 5-7, 8a,d,e, 9a-d, 10c,d, 11, 13, 14 • Activity Series Worksheet • Concept Review, “Classifying Chemical Reactions”
Homework Questions • Sec. 8.3 review, pg 285: • 1-4, 8b,c,f, 10a,b,e,f, 12 • Practice box, pg. 279: #1-4
5 Types of Chemical Reactions • Combustion • Synthesis (sometimes called combination) • Decomposition • Single Displacement • Double Displacement
Single Displacement Reactions • Single Displacement Reaction: a reaction in which a single element reacts with a compound and displaces another element from the compound. • Products are a different element and a different compound than the reactants • In general, a metal may displace another metal, or hydrogen, while a non-metal may displace only another non-metal 2 Al(s) + 3 CuCl2(aq) 2 AlCl3(aq) + 3 Cu(s) (Al displaces Cu)
The Activity Series Ranks Reactivity • How do you know whether an element will replace another element or not? • Use the activity series table… • Activity Series: a series of elements that have similar properties and that are arranged in descending order of chemical reactivity.
Activity Series • Elements are arranged in order of activity with the MOST ACTIVE at the top. • In general, an element can displace those listed BELOW it from compounds in solution, but NOT those listed above it. • The activity series can be used to make predictions about displacement reactions. • When a metal is placed in water, the activity series will help tell if hydrogen is displaced. If this happens, a metal hydroxide and hydrogen gas will form.
Sample Problem E, Pg. 282Determining Products by Using the Activity Series Magnesium is added to a solution of lead(II) nitrate. Will a reaction happen? If so, write the equation and balance it. • Reactants: Magnesium, Mg, and lead (II) nitrate. • What is the formula for lead (II) nitrate? Pb2+ NO31- Pb(NO3)2
Sample Problem E, Pg. 282Determining Products by Using the Activity Series, cont. Mg + Pb(NO3)2 ? • Check the activity series: Mg is MORE reactive than Pb, so it WILL displace Pb. Mg + Pb(NO3)2 Mg(NO3)2 + Pb • Lastly, balance the equation: It already is!
Additional Example If the reaction happens, write a balanced equation if sodium is placed in cold water. • Reactants: Sodium, Na, and cold water, H2O. • Check the activity series: Na reacts with cold water to displace a hydrogen atom Na + H2O NaOH + H2 • Lastly, balance the equation: 2 Na + 2 H2O 2 NaOH + H2
Additional Example If the reaction happens, write a balanced equation for the reaction if gold is added to a solution of calcium chloride. • Reactants: Gold, Au, and calcium chloride, CaCl2 • Check the activity series: Gold is LESS reactive than Ca, so it WILL NOT displace Ca – no reaction happens. Au (s) + CaCl2 (aq) = No Reaction!
Double Displacement Reactions • Double displacement reaction: a reaction in which a gas, a solid precipitate, or a molecular compound forms from the apparent exchange of atoms or ions between compounds. • 2 compounds appear to exchange ions and form 2 new compounds • One of the products must be a solid precipitate, a gas, or a molecular compound, such as water. (see table) • Water is often written as HOH in these reactions.
Identifying Reactions and Predicting Products Pg. 284 in your textbook has a really nice skills toolkit to help identify reaction types and predict products. If product is not soluble, it will be a solid precipitate.
Double Displacement Reactions HCl(aq) + NaOH(aq) HOH(l) + NaCl(aq) • When solutions of hydrochloric acid, HCl, and sodium hydroxide, NaOH, are mixed, a double displacement reaction occurs, creating a molecular compound, water, and sodium chloride.
Double Displacement Reaction Example Predict the products and write a balanced equation when solutions of sodium sulfate and strontium nitrate are mixed. Na+ SO42- Sr 2+ NO31- Na2SO4 Sr(NO3)2 • Reactants: Na2SO4 (aq) and Sr(NO3)2 (aq) • This is a double displacement reaction so the 2 compounds will switch ions…
Double Displacement Reaction Example, cont. Na2SO4 (aq) + Sr(NO3)2 (aq) ? Na+ NO31- Sr2+ SO42- NaNO3 (aq) SrSO4 (s) Na2SO4 (aq) + Sr(NO3)2 (aq) NaNO3 (aq) + SrSO4 (s) • Lastly, balance equation: Na2SO4(aq) + Sr(NO3)2 (aq) 2 NaNO3(aq) + SrSO4(s)
Additional Example Predict the products and write a balanced equation when solutions of potassium carbonate and iron (III) chloride are mixed. K+ CO32- Fe3+ Cl1- K2CO3 FeCl3 • Reactants: K2CO3 (aq) and FeCl3(aq) • This is a double displacement reaction so the 2 compounds will switch ions…
Additional Example, cont. K2CO3 (aq) + FeCl3(aq) ? K1+ Cl1- Fe3+ CO32- KCl (aq) Fe2(CO3)3 (s) K2CO3 (aq) + FeCl3(aq) KCl (aq) + Fe2(CO3)3 (s) • Lastly, balance equation: 3 K2CO3 (aq) + 2 FeCl3(aq) 6 KCl (aq) + Fe2(CO3)3 (s)
Homework • Wow guys, I know we covered a lot of material in this section, but you guys stayed with me! • Section 8.3 review, pg. 285: #5-7, 8a,d,e, 9a-d, 10c,d, 11, 13, 14 • Activity Series Worksheet • Concept Review: “Classifying Chemical Reactions”
Looking Ahead • Tuesday/Wednesday: • Finish Chemical Formulas/Equations worksheet • 8.3 Quiz:“Classifying Chemical Reactions” • Lab write-up (you’ll need your lab folder!) • Thursday/Friday: • Lab: “Classifying Chemical Reactions”