indications of a chemical reaction. what do we look for to determine if a chemical reaction is...
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Indications of a Chemical Reaction
What do we look for to determine if a chemical reaction is occurring?
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light– The burning of wood or coal
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light– The burning of wood or coal– The burning of magnesium
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light– The burning of wood or coal– The burning of magnesium– This is not always an indication of a chemical
reaction.
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light– The burning of wood or coal– The burning of magnesium– This is not always an indication of a chemical
reaction.• Phosphorescence or fluorescence produce light
without a chemical reaction.
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light– The burning of wood or coal– The burning of magnesium– This is not always an indication of a chemical
reaction.• Phosphorescence or fluorescence produce light
without a chemical reaction.• Compression of gases produce heat without a
chemical reaction.
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas
– Gas bubbles when two things are mixed
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas
– Gas bubbles when two things are mixed• Zinc and acid
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas
– Gas bubbles when two things are mixed• Zinc and acid• Baking soda and vinegar
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas• Formation of a precipitate
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas• Formation of a precipitate
– A solid formed when mixing two things
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas• Formation of a precipitate
– A solid formed when mixing two things• Zinc sulfate and barium nitrate
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas• Formation of a precipitate
– A solid formed when mixing two things• Zinc sulfate and barium nitrate• Potassium iodide and lead nitrate
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas• Formation of a precipitate
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas• Formation of a precipitate• Color change
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas• Formation of a precipitate• Color change
– Rusting causes iron to go from silvery to red
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas• Formation of a precipitate• Color change
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas• Formation of a precipitate• Color change• Formation of water
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas• Formation of a precipitate• Color change• Formation of water
– Burning hydrocarbons produce carbon dioxide and water.
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas• Formation of a precipitate• Color change• Formation of water
– Burning hydrocarbons produce carbon dioxide and water.
– Combining acids and bases form water.
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas• Formation of a precipitate• Color change• Formation of water
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas• Formation of a precipitate• Color change• Formation of water
– The formation of water does not necessarily indicate a chemical reaction.
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas• Formation of a precipitate• Color change• Formation of water
– The formation of water does not necessarily indicate a chemical reaction.
• Water condenses on a cold glass.
What do we look for to determine if a chemical reaction is occurring?
• Evolution of heat and light• Production of a gas• Formation of a precipitate• Color change• Formation of water