All About Energy
True or False:
Energy is a type of matter.
False! Energy is not matter.
Do endothermic reactions tend to be hot or cold
Endothermic reactions are cold
Do exothermic reactions tend to be hot or cold?
Exothermic reactions tend to be hot.
True or False:
All chemical reactions change temperature.
False!
What tool is used to measure temperature
A thermometer
What is the official definition of energy?
Energy is the ability to cause change or do work.
Fill in the blank:
Ice packs work because energy is ________________ from the system.
Words: Absorbed, Released, Created, Destroyed
Absorbed!
Fill in the blank:
Hand warmers work because during the chemical reaction energy is ______________ from the system.
Words: Absorbed, Released, Created, Destroyed
Released!
Why might we want to understand chemical reactions and what they do.
It can help us create solutions to problems we may have (ice packs, heat packs, MRE's).
So we know where energy is going or coming from.
It can also help us understand how things interact with each other.
What are some ways humans get energy?
Eating, Drinking, Sleeping
What is the Law of Conservation of Energy?
Energy cannot be created or destroyed, only transformed.
Fill in the blank:
Endothermic reactions ____________ energy.
Words: Absorb, Release, Create, Destroy
Endothermic reactions absorb energy
Fill in the blank:
Exothermic reactions ___________ energy.
Words: Absorb, Release, Create, Destroy
Exothermic reactions release energy
What happens to the molecules during a chemical reaction?
The molecules break apart and rearrange
Temperature change is a _____________ change.
Words: Physical, chemical, energy
Physical change! (cause by a chemical reaction)
True or false:
Energy can move between a reaction and its surroundings.
True!
Provide an example of something that has an endothermic reaction
Ice packs, baking soda and vinegar, melting ice...
Anything that makes surroundings colder
Provide an example of something that is an exothermic reaction.
Hot packs, rusting, boiling water...
Anything that makes surroundings warmer
What does a temperature change in a chemical reactions tell us?
It tells us that energy is being used or released during the reaction.
What is thermal energy?
Energy that relates to temperature or heat.
What are the three types of energy transfers?
Conduction, Convection, Radiation
Where is the energy going during an endothermic reaction
The energy is moving into the reaction (being absorbed), taking energy from the surrounding area.
Where is the energy coming from in an exothermic reaction?
Energy is being released from the molecules during an exothermic reaction. These molecules don't need all of the energy so they get rid of it during the reaction.
What kind of reaction do the MRE's packs use?
They use heat packs that have an exothermic reaction.
True or False:
Chemical reactions always involve energy changes.
True!