Indications of 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 –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