chem. reactions

What does not indicate a chemical reaction has occurred?

• A change in color

• Mixing ingredients

• Emission of odor

• Production of a gas

What might you notice if a chemical reaction produces a gas?

• Bubbles forming

• A change in color

• A new smell

• A solid forming

What is a sign that a chemical reaction has occurred when baking cookies?

• The batter stays the same color

• The batter becomes colder

• The cookies emit a pleasant aroma

• The cookies remain flat

What is a precipitate?

• A type of gas

• A liquid mixture

• An insoluble solid

• A color change

Which of these is an example of a precipitate?

• Melted ice

• Steam from boiling water

• Soap scum in a bathtub

• Bubbles in soda