February 23, 2011- Review

AWW YEAH I CAN BLOG AGAIN.

Thanks to Edmond taking everything I needed to blog about, I'm going to talk about our test next class.

The test next class will be on all of chapter 5, which includes chemical reactions (Single Replacement, Double Replacement, Synthesis, Decomposition, Combustion and Neutralization), balancing chemical equations, and endothermic or exothermic equations.

February 16, 2011- Endothermic and Exothermic

Exothermic and Endothermic Reactions

-chemical reaction involves change in energy (Delta H)

-exothermic (release of energy)

-endothermic (absorb energy)

-eg. instant ice pack (endothermic)

explosion (exothermic)

Molecules held together by chemical bonds

-add energy to break bonds

-release energy to form bonds

Exothermic

-reactant's energy > product's energy

-energy is released during the chemical reaction

Endothermic

-reactant's energy <>-energy is absorbed during the chemical reaction

Enthalpy(the heat within a contained system)

- (product's energy) - (reactant's energy) = Delta H

+ Delta H ==> Endothermic

- Delta H ==> Exothermic

Energy Diagram

-allows to chart potential energy and the product's energy

-the Energy is based on Delta H

Important Terms

-Potential Energy (kJ) y intercept

-Reaction Progress x intercept

-Activated complex = the peak of every energy diagram

-Activation Energy = the energy required from reactant to activated complex

Some helpful videos

Endothermic and Exothermic Reactions

Feb 08 2011 - Types of Reaction

We reviewed the note which is about double replacement, combustion, neutralization and net ionic equations.

Double replacement

AB + CD -> CB+ AD

Eg. Na2CO3 +2KBr -> K2CO3 +2NaBr

Combustion

AB + O2 -> AO + BO

Eg. C4H8 + 6O2 -> 4CO2 + 4H2O

Neutralization

HA + BOH -> H2O + BA

Eg. HBr + Sr(OH)2 -> SrBr2 + 2H2O

Net Ionic Equations

Eg. KCl + AgNO3 -> KNO3 + AgCl

Total ionic equation : K+ (aq) + Cl-(aq) + Ag+(aq) + NO3-(aq) -> K+(aq) + NO3-(aq) + AgCl(s)

Net ionic equation : Ag+(aq) + Cl-(aq) -> AgCl(s)

February 4, 2011- Lab 5B

Today we did the Lab 5B,

Where we experimented with various solutions and solvents to produce various chemical reactions.

For example, double replacement, single replacement, combustion, neutralization, decomposition and synthesis.

There were at total of 7 Reactions in total that was in the Lab 5B.

A lab report was also mandatory to be completed, we were able to have a total of 2 classes to finish the lab report.

Having to do the conclusion which involved a chemical formula for each of the 7 reaction, and the following up questions with analyze questions.

Testing with various substances with solvents to create reactions and even a precipitate.

Example of one type of reaction we done :

a youtube channel that has various videos on chemical reactions:

http://www.youtube.com/user/Papapodcasts