Heats of Reaction
physical or chemical properties
Is it a chemical change, or physical?
Signs of a Chemical Change
classify the reaction
100
This kind of reaction absorbs energy.
What is an endothermic reaction?
100
Density is this type of property.
What is a physical property?
100
You cut a piece of paper in half.
physical
200
This kind of reaction emits energy to it's surroundings.
What is an exothermic reaction?
200
This type of property relates to how substances interact with each other.
What is a chemical property?
200
A piece of paper is folded.
physical
300
Fire is an example of this type of reaction.
What is an endothermic reaction?
300
Characteristics such as color, conductivity, density, and texture are examples of this type of property.
What is a physical property.
300
A piece of paper burns.
chemical
400
Do endothermic reactions require a MORE or LESS activation energy than exothermic reactions?
more
400
This type of property cannot be observed without changing the characteristics of the substance.
What is a chemical property?
400
A nail rusts
chemical
500
An endothermic reaction takes place in a beaker of water. Where did the activation energy come from?
the heat of the water
500
Salt is added to water to form salt water.
physical
500
List the 5 signs of a chemical change
1. color change, 2. gas, 3. change in smell or taste, 4. change in temperature, 5. precipitate.
500
Draw a synthesis, decomposition, and replacement reaction (in order from top to bottom) using up to three elements represented by X and O and Z and Y.
X + O => XO XO => O + X XO + ZY => XY + ZO (one example)
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