Today in Chemistry we performed a lab that had 11 different experiments that had to be performed to show us the different types of chemical reactions that occur. There are three major indicators that tell us if they are true chemical reactions, which include: a precipitate forming, color change and the appearance of bubble/fizzing. During each mini lab at least one of each indicators was seen, for example me and my partner performed reactions 5 and 8 which was assigned to us by our teacher. Reaction number 5 resulted in turning a milky white, became increasingly hot and had big bubbles that kept fizzing out and in reaction number 8 it turned a bright yellow color. I believe that the products of reactants can be predicted because the atoms in the reactants are the same, so the outcome will always be the same.The reactions were divided up into five sections: Section 1 (Reactions 1 and 2); Section 2 (Reactions 3 and 4); Section 3 (Reactions 5 and 6); Section 4 (Reactions 7, 8 and 9); and Section 5 (Reactions 10 and 11).
This was done based on similarity:
Section 1: Two reactants that produced one product. Ex: 4Fe+302=2Fe203 Section 2: One reactant that produced two or more products. Ex: 2H202=2H20+02 Section 3: One element or ion is replaced by another element/ion in a compound. Ex: Zn+Pb(NO3)2=Pb+Zn(NO3)2 Section 4: Two compounds exchanged their elements/ions for those of the other compound. Ex: Pb(NO3)2+2KI=2KNO3+PbI2 Section 5: Combustion. Ex: CH4+O2=CO2+2H2O
Here are the balanced chemical equations for the 11 chemical reactions:
1. 4Fe(s) + 3O2(g) –> 2Fe2O3(s)
2. CaO(s) + H2O(l) –> Ca(OH)2(aq)
3. 2H2O2(l) —MnO2–> 2H2O(l) + O2(g)
4. 2NaHCO3(s) –> H2O(l) + Na2CO3(s) + CO2(g)
5. Ca(s) + 2H2O –> H2(g) + Ca(OH)2(aq)
6. Zn(s) + Pb(NO3)2(aq) –> Pb(s) + Zn(NO3)2(aq)
7. Na2CO3(aq) + Ba(NO3)2(aq) –> 2NaNO3(aq) + BaCO3(s)
8. Pb(NO3)2(aq) + 2KI(aq) –> 2KNO3(aq) + PbI2(s)
9. CaCO3(s) + 2HCl(aq) –> CO2(g) + H2O(l) + CaCl2(aq)
10. CH4(g) + 2O2(g) –> CO2(g) + 2H2O(g)
11. 4C2H5O2(l) + 9O2(g) –> 8CO2(g) + 10H2O(g)
Ca(s) + 2H2O –> H2(g) + Ca(OH)2(aq)
Pb(NO3)2(aq) + 2KI(aq) –> 2KNO3(aq) + PbI2(s)
Sources:
Lab Notebook/Notes
Lab Results
In Class Discussion