unit vi: chemical reactions i.5. types of chemical reactions

Unit VI: CHEMICAL REACTIONS

I.5. Types Of Chemical Reactions

Types of Reactions

1. Synthesis2. Decomposition3. Single Replacement4. Double Replacement

Neutralization (Water Forming)

5. Combustion1. Combustion of hydrocarbons2. Combustion of metals

Synthesis

Two or more substances combine to form a compound

A + B → AB

Synthesis

Synthesis

Often: elements a compound

2Al + 3F2 2AlF3

Synthesis

Examples 2H2 + O2 → 2H2O

2Mg + O2 → 2MgO

CaO + CO2 → CaCO3

Synthesis

potassium + oxygen

calcium + phosphorous

Synthesis

A special type of synthesis

CoCl2 + 6H2O CoCl2● 6H2O

Synthesis

A compound + an element a “bigger” compound

2SO2 + O2 2SO3

Synthesis - Overview

Always more more than 1 reactantthan 1 reactant

Usually forms only 1 productonly 1 product

Decomposition

One substance breaks down into more than one substance

AB → A + B

Decomposition

Decomposition

EXAMPLES: 2HgO → 2Hg + O2

2H2O → 2H2 + O2

MgCl2→ Mg + Cl2

Decomposition

Note: Unless otherwise told, break all compounds COMPLETELY down to its elements. (Even break up PAIs)

Decomposition

Note: Unless otherwise told, break all compounds COMPLETELY down to its elements. (Even break up PAIs)

Decomposition

Note: Unless otherwise told, break all compounds COMPLETELY down to its elements. (Even break up PAIs)

Decomposition

A special type of decomposition

CuSO4● 5H2O CuSO4 + 6H2O

Decomposition

AlsoA Bigger Compound Smaller Compound + An Element

2KClO3 2KCl + 3O2

Single Replacement

One substance replaces another in a compound Metals replace metals Non-metals replace non-metals

AB + C → A + BC

Single Replacement

Single Replacement

Two Types1. Metal Single Replacement

2. Non-metal Single Replacement

Single Replacement

Examples of Metal SR

Zn + CuSO4 → Cu + ZnSO4

Fe + 3AgNO3 → 3Ag + Fe(NO3)3

Single Replacement

Metal SRs

Single Replacement

Metal SRs

Single Replacement

Some Non-Metal SRs

Single Replacement

Some Non-Metal SRs

Single Replacement

The catch some elements are not strong enough to replace others

Plan:1. Predict Products2. Fix Formulas3. Balance Equation4. Determine from Activity Series if

Reaction will Proceed

Double Replacement

Both compounds change partners

Again refer to the activity series to see if reaction will proceed

AB + CD → AD + BC

Double Replacement

Double Replacement

Refer to the activity series to determine the relative reactivity of elements. For example, calcium is more reactive than hydrogen; therefore, calcium can replace hydrogen in a reaction.

Ca(s) + 2 HOH(l) Ca(OH)2(s) + H2(g)

Double Replacement

Examples: 2KI(aq) + Pb(NO3)2(aq) → 2KNO3(aq) + PbI(s)

AgNO3 + KCl → AgCl(s) + KNO3

Double Replacement

Double Replacement

Double Replacement

Neutralization

Sub-type of Double Replacement Reaction

Sometimes called water forming

ACID + BASE → WATER + SALT

Neutralization

Neutralization

Combustion (aka Burning Stuff)

Substance reacts with oxygen (fast enough to produce heat and light)

Two Types of Combustion1. Combustion of hydrocarbons

2. Combustion of metals

Combustion

Hydrocarbons NOTE: O2 is ALWAYS A REACTANTALWAYS A REACTANT! When burning hydrocarbons ASSUMEASSUME

the products are

CO2 + H2O

Combustion

CxHy + O2 → CO2 + H2O

Combustion

Combustion

Combustion

Combustion of Metals = Synthesis

Combustion

Combustion of Metals = Synthesis

Combustion

Combustion of Metals = Synthesis

Assignments

Do Problem Set #3 and #4 on page in your Student Workbook

Do Exercises 65 (a, c, e), 66 (b, d, f, h, j, l, n, p, r, t, v, x), 67 (a, c, e, h, j, l, n, p, r) on page 118 [Hebden]

Do Hand-In Assignment # 8

Lab

Do Experiment 5C – page 71-73[Heath] This experiment will take most of the

class your pre-lab must be complete beforebefore the lab begins

Fill in the Blank Lab Format you are only responsible for the questions asked in the lab handout