1. 7.5 Neutralization Reactions
SNC 2D1
Mr. Dvorsky
March

2. Yet another type of reaction...
A neutralization reaction occurs when an acid and a base react to form products that have a pH closer to 7 than either of the reactants.

3. Acids form hydrogen ions in water, and bases release hydroxide ions.
When acids and bases are mixed, the two ions react to form water

4. Predicting the Products of Neutralization Reactions
If we know the reactants of a neutralization reaction, we can predict the products
AB + CD  AD + CB
For example:
HCl (aq) + NaOH (aq)  H2O (l) + NaCl(aq)
This is an example of a
double displacement reaction

5. H2S04 (aq) + 2KOH (aq)  2H20 (l) + K2SO4(aq) water salt (ionic compound) -notice that two units or molecules are needed for each H2S04 molecule -this makes sense! Each H2S04 can release two H+ ions into solution, so there are two OH- to react with

6. Chemical Spills
In March 2007 a train hauling L of sulfuric acid derailed in Englehart northern Ontario.
The sulfuric acid killed fish, and posed a threat to both humans and wildlife
Emergency response crews added calcium oxide CaO(s) to the river to neutralize the acid
Ca(s) + H2O(l)  Ca(OH)2 (aq)
Ca(OH)2 + H2SO4(aq)  2H2O(l) + CaSO4(aq)

7. Chemical Spills
In October 2010, a wall holding a pond of toxic sludge gave way and caused a flood of toxic sludge. A large component of the sludge was sodium hydroxide – very basic. -the sludge leaked into the river system. -acid was used to help neutralize the sludge

8. Writing a Science Report
The Introduction -this section must include a statement of purpose, a hypothesis, and some background information. -in this lab the background information will be about the law of conservation of mass. -use present tense

9. Writing a Science Report
Procedure: Write “The procedure was followed as per page 228 and 229 of Nelson Science Perspectives 10 with the following changes:” -list the changes e.g. We used Hydrogen Chloride [HCl(l)] instead of Iron (III) Nitrate. We used phenolphthalein as a pH indicator so that we could detect that the neutralization reaction had taken place

10. Materials -list what is required to conduct the investigation, omit what we didn’t use and add what we did. Observations: Present all tables whether they support your prediction or not. Include the class averages.

11. Conclusions: One sentence for both Part A and Part B concluding on the results of the study. Two sentences discussing whether or not the results support your hypothesis. One sentence on sources of error or biases in the study.

12. Homework
Page 281 #1-5