Center for Power Optimization of Electro-thermal Systems
Infant Incubator Lesson 5
What patterns are present when a chemical reaction occurs?
Optional: "Measurement with SI Units"
Estimated class Time:
Two 40 minute class periods
How can you determine if a chemical reaction occurs? What patterns?
- Metric Balance
- Small scoop of table salt
- Alka seltzer tablet
- 1 cm of magnesium ribbon
- Dropper full of hydrochloric acid
- Dropper full of silver nitrate
- Paper towels
- Test tube
- CER videos (found in resource file)
- CER organizer
Lesson Level Learning Objectives:
- MS-PS1-2: Analyze and interpret data on the properties of substances before and after the substances interact to determine if a chemical reaction has occurred.
- Students conduct a variety of chemical reactions (unexpected color change, unexpected temperature change, production of gas, formation of a precipitate) and record their observations. The observations are used to generalize patterns and begin to define chemical changes.
What we Figured Out:
- In a chemical change new substances are formed.
- The clues that a chemical reaction has taken place are unexpected color change, unexpected change in temperature, unexpected gas production, unexpected property change and a formation of a precipitate.
- In a physical change, the substances might look different in size or shape only, but it is still the same substance.
- Exothermic reactions - a process that releases heat and causes the temperature to rise.
- Endothermic reactions - a process that absorbs heat and cools the surroundings.
Questions we still have:
- Why do some reactions take longer than others?
- Does it matter how much of each chemical we use?
- Can we stop a reaction?
- Can we control how long a reaction takes?