Types of Reaction and Predicting Reactions

Concept PresentationWinnie Ho HS Science

Instructors Janine Extavour & Marty Zatzman

Goal of this presentation

Grade 10 teachers:- Differences between Gr 10 and 11

and how to prepare our students

Grade 11 teachers:- What Gr 10 students know and

common roadblocks in this topic

Teaching sequence in 11U

•Unit 1- Matter, Chemical trends, and Chemical Bonding

•Unit 2 - Chemical reactionPrior knowledge: - Ionic compounds and covalent

molecules - Nomenclature - Balancing equation - Classifying reactions

Curriculum expectationGrade 10 – Chemistry expectations on types of reaction

C2.3investigate simple chemical reactions, including synthesis, decomposition, and displacement reactions, and represent them using a variety of formats (e.g., molecular models, word equations, balanced chemical equations)

C3.5 describe, on the basis of observation, the reactants in and products of a variety of chemical reactions, including synthesis, decomposition, and displacement reactions (e.g., reactions occurring when magnesium burns or in the production of oxygen from hydrogen peroxide; the reaction of iron and copper sulphate; reactions occurring when fossil fuels burn)

Grade 11 – Chemical reaction (selected expectations on types of reaction)

C2.4predict the products of different types of synthesis and decomposition reactions (e.g., synthesis reactions in which simple compounds are formed; synthesis reactions of metallic or non-metallic oxides with water; decomposition reactions, in which a chemical compound is separated into several compounds)

C2.5 predict the products of simple displacement reactions, using the metal activity series and the halogen series.

C2.6 predict the products of double displacement reactions (e.g. formation of precipitates or gases; neutralization)

C2.7 design an inquiry to demonstrate the difference between a complete and an incomplete combustion reaction

C2. 10 plan and conduct an inquiry to demonstrate a simple displacement reaction, using elements from the metal activity series

C3.1 identify various types of chemical reactions, including synthesis, decomposition, single displacement, double displacement, and combustion

Comparison

Grade 10- Classifying all four

reaction types+ Neutralization

Grade 11- All four reaction

types+ Activity series+ Solubility rules+ Neutralization+ Combustion+ Nuclear reactions

• Focus on lab inquiry • Prediction of

products

Diagnostic assessment1. nitric acid + potassium hydroxide ____________+

water Type: ___________2. zinc + ___________ zinc nitrate solution + copper

Type: ___________3. __________ acid + zinc carbonate zinc sulfate +

water + carbon dioxide Type: ___________4. calcium + chlorine _____________________

Type: ___________5. magnesium + hydrochloric acid __________ +

hydrogen Type: ___________6. propane + oxygen _____________________ + water

Type: ___________

Reaction Type General Chemical Equation

Synthesis A + B AB

Decomposition AB A + B

Single Displacement

M + BC MC + B

N + BC BN + C

Double Displacement AB + CD AD + CB

Combustion CxHy + _O2 _ CO2 +_ H2O

+

+

++

++

++

Sodium and Chlorine reacts to form Sodium chloride

Roadblock #1Failure to connect symbols to the actual elements

A + B AB

A can represent an element, a diatomic molecule, or a compound.

The ordering of the symbols is important.

Can you find the mistakes?

Macroscopic

Microscopic

Symbolic

Roadblock #2Predicting synthesis vs. combustion rxn

Grade 10 – synthesis reaction Grade 11 –combustion reaction

•Reaction of a substance with oxygen, producing oxides and energy (Nelson text)

•Combustion of magnesium as an example of a synthesis reaction

•Exothermic reaction

Synthesis Reaction!

Brad + Angelina Brangelina

Tom + Katie TomKat

Roadblock #3Predicting single displacement reactions

Zn(s) + CuSO4(aq)-->ZnSO4(aq) + Cu(s)

Video

Safety concerns:

Demo: Li, Na, K with water

Goggles, small quantity

Alternatives

M + BC MC + B

M= metal element

N + BC BN + C

N= non-metal element

Roadblock #4Predicting double displacement reactions

If a reaction does not produce a precipitate, a gas, or water, then it is not a DD reaction.

Solubility table

KOH(aq) + NH4Cl (aq)--> No Reaction

KOH(aq) + NH4Cl (aq)--> no reaction

Use of states symbols are important

• More consistent usage of state symbols in grade 10 when writing out chemical equations.

e.g., NaOH(aq) + HCl(aq) H2O (l) + NaCl (aq)

Societal implications

Synthesis reaction Rusting, Galvanization, Alloy

Decomposition reaction

Production of sodium using electrolysis of molten sodium chloride

Single displacement reaction

Extracting metals, smelting process, Bromine compound as fire retardant

Double displacement reaction

Geochemistry (solubility rules allows students to understand why some elements exist as compounds in nature), corrosion of statues

Combustion Greenhouse effect

Computer resources• Gizmos

• Metals in aqueous solutions simulation

Differentiated instruction• Computer simulation (modified

versions of activities)• Video• Group work on making connections

issues

Thank you.