Quick Write! You have 6 minutes! Describe the 4 main types of Chemical Reactions, as demonstrated in class, using the following components: Peanut butter Chocolate Graham Cracker Almonds
Physical Science 1-24-07 Review Practice Team Work! Introduction to Balancing Formulas
REVIEW • What are the components of a chemical reaction? ________ + __________ _________ Reactant Reactant Product What does the arrow mean in the equation? “Forms” , “ Produces” , or “ Yields”
REVIEW • What type of Chemical Reaction does this photo represent? Double Displacement Reaction
REVIEW • How about this one? Synthesis Reaction
REVIEW • What type of reaction does this photo represent? Single Displacement Reaction
REVIEW • And the last one we modelled? Decomposition Reaction
REVIEW • In what type of reaction does oxygen react with a second compound producing CO2 and H2O ? COMBUSTION Reaction
Team Work! • Please locate your team members and quickly sit at one of the back 4 tables together. • Team A: Sara, Christian, Carl, Justin, & Bill • Team B: Joe, Ashlee, Courtney, & Tiffany • Team C: James D., Brittney, Chelsey, Garrett, & Tim • Team D: Lacy, James E., Kayla, & Brandon
Team Work! • Each team is provided with a set of 5 cards (one for each type of reaction we have studied). • Each slide that is projected here will display a new chemical reaction. • As a team you have 20 seconds to decide which type of reaction it is and place that card, FACE DOWN, at the end of the table closest to the teacher. • If you are correct, your team may talley one point on the chalk board. If you are incorrect, your team loses two points!!!!
H2 + Cl2 2HCl Synthesis Reaction
4H2 + O2 2H2O Synthesis Reaction
2CH4 + 3O2 2CO2 + 4H2O Combustion Reaction
2Al + 2H2SO4 Al2(SO4 ) 2 + 2H2 Single Displacement Reaction
2Al2O3 4Al + 3O2 Decomposition Reaction
SiCl4 Si + 2Cl2 Decomposition Reaction
C + 2H2 CH4 Synthesis Reaction
Zn(OH)2 ZnO + H2O Decomposition Reaction
2KI + Cl2 2KCl+ I2 Single Displacement Reaction
Mg + 2HCl MgCl2 + H2 Single Displacement Reaction
P4 + 5O2 P4O10 Synthesis Reaction
GAME OVER! • TALLEY UP THE POINTS EACH TEAM HAS…THE WINNING TEAM RECEIVES A PRIZE AT THE END OF CLASS.
WHAT ELSE CAN WE LEARN USING THESE REACTIONS? • C + 2H2 CH4 • HOW MANY ATOMS ARE THERE ON THE LEFT SIDE OF THE REACTION (TOTAL)? • HOW MANY ATOMS ARE THERE ON THE RIGHT SIDE OF THE REACTION (TOTAL)?
C + 2H2 CH4 • On the left side, there are ONE Carbon atom and FOUR Hydrogen atoms. (Note: 4 Hydrogen atoms, because the Coefficient gets multiplied by the subscript). This gives us 5 total atoms. • On the right side (products), we also see ONE Carbon atom and FOUR Hydrogen atoms, for a total of 5 atoms. • Notice that the number of atoms of each ELEMENT stays the same on each side!
This is known as a BALANCED EQUATION!
Over the next couple of days, we will be discovering how to balance a chemical equation by manipulating the Coefficients. • It is important to remember that we will not change the subscript numbers in the formulas at any time. (*Few exceptions to this rule may be pointed out later to you.) • Bring your books, your thinking caps and a writing utensil tomorrow….and find out more!!!
