Get Ready! Today’s Agenda 5-in-5 Rate of Reaction Notes Lab Materials Today’s Agenda Pencil Notebook 5-in-5 Rate of Reaction Notes Lab Exit Ticket FCA #3 on Block Day
5-in-5 #37 Find the volume of the rock. Explain how you find the volume of an irregular solid using water displacement.
Lesson Frame Essential Question: How does a change in temperature affect the rate(speed) of a reaction? I will… Know how increasing the temperature affects the rate of the reaction By the end of this lesson I will be able to… Explain why a temperature increase also increases the rate of the reaction.
Factors Affecting Rate of Reaction
Fill the rest of the page! Rate of Reaction: Concentration Surface Area Fill the rest of the page! Presence of a Catalyst Temperature
Rate of Reaction: Chemical reactions occur at different rates (speeds) The rate of reaction can be changed by: Concentration Surface Area Presence of a catalyst Temperature
Concentration How does the concentration of a solution affect the rate of reaction? How will different concentrations (strengths) of hydrochloric acid dissolve magnesium? Reaction: Mg + HCl MgCl2 + H2 Predictions? Materials per table: 2 test tubes, 2 (2 cm) pieces of magnesium strip, hydrochloric acid (2 concentrations – one full strength and one diluted), stopwatch (optional)
Concentration Concentration: the amount of a substance (solute) present in a given volume of solution “Packing” in more molecules increases the number of collisions Therefore a more concentrated solution = increased rate of reaction Rate of Reaction Concentration
Surface Area How does surface area affect the rate of reaction? How does surface area affect the rate of reaction of alka-seltzer with water? (Whole vs. crushed) Reaction: 3HCO3 + 3H → 3H2O + 3CO2 Predictions? Materials per table: 2 test tubes, 1 alka tablet (cut in half) (used one half and crush the other half), water, hammer, stopwatch (optional)
Surface Area The smaller the size of the particles, the greater the surface area that the reaction can take place in Therefore, increase surface area = increased rate of reaction Rate of Reaction Surface Area
Day 2 - Continued
Get Ready! Today’s Agenda 5-in-5 Rate of Reaction Notes (Finish) Lab Materials Today’s Agenda Pencil Notebook 5-in-5 Rate of Reaction Notes (Finish) Lab Exit Ticket FCA #3 on Block Day
5-in-5 #38 If a rock was cut into four identical pieces, the density of each piece compared to the density of the original rock would be: Less Greater The same ¼ of the original density Choose your answer and explain why you chose that answer. You could also discuss why you DIDN’T pick the other three answers.
Lesson Frame Essential Question: How does a change in temperature affect the rate(speed) of a reaction? I will… Know how increasing the temperature affects the rate of the reaction By the end of this lesson I will be able to… Explain why a temperature increase also increases the rate of the reaction.
Catalyst How does the addition of a catalyst effect the rate of reaction? Which solution will act as a catalyst effect the decomposition of hydrogen peroxide? Reaction: 2H2O2 → 2H2O + O2 Predictions? catalyst Materials per table: 1 test tubes, hydrogen peroxide, yeast solution (make ahead), Pipette, 1 drop of dishsoap, food coloring (optional), stopwatch (optional)
Catalyst Substance that enhances the rate of chemical reaction without being consumed itself A catalyst is NEITHER a reactant or a product! A catalyst decreases the amount of energy needed to break bonds and form new ones Therefore, presence of catalyst = increased rate of reaction
Temperature How does the temperature affect rate of reaction? How does the temperature of water affect the rate at which an glow stick light up? Reaction: H2O2+ C14H10O4 + dye C6H2Cl3OH + 2CO2 + light Predictions? Materials per table: 2 test tubes, 2 glow sticks, hot water and ice water, stopwatch (optional)
Temperature Increases energy of particles due to increase of temperature Increase speed of particles and there are more successful collisions because molecules to contact one another more readily and with harder force Therefore increased temperature = increased rate of reaction Rate of Reaction Temperature
Exit Explain what happens to the particles in a reaction when the temperature is increased and why this causes the reaction to speed up.
Get Ready! Today’s Agenda 5-in-5 Quick Review FCA #3 FCAT Review Materials Today’s Agenda Pencil Notebook Scrap paper 5-in-5 Quick Review FCA #3 FCAT Review FCA #3 Today
5-in-5 #39 You have two sheets of paper. You tear one sheet of paper into tiny pieces and you burn the second piece of paper. Part A: Identify if tearing a sheet of paper is a chemical or physical change AND explain why. Part B: Identify if burning a sheet of paper is a chemical or physical change AND explain why. Part C: What is the law of conservation of mass?
Quick Review: Physical and Chemical Changes Ice melting Tarnishing of silverware Breaking concrete into pieces Burning wood in a fireplace Rusting nail Salt dissolving in water Food digesting in your stomach
Quick Review: Density What is the formula for density? Determine if each object would float or sink in water. Which object is the most dense? Mass Volume Object A 19.3 g 40 mL Object B 34.9 g 24 mL Object C 100 g
FCAT Review Week One 7th Grade: Cells, Organelles and the Human Body