Physical and Chemical Changes

What are physical properties of matter?

• Taste, smell, sound, flexibility

• Weight, volume, texture, hardness

• Temperature, pressure, magnetism, transparency

• Color, shape, size, density, melting point, boiling point, conductivity

What is a chemical reaction?

• A chemical reaction is a process that leads to the destruction of chemical substances.

• A chemical reaction is a process that leads to the transformation of one set of chemical substances to another.

• A chemical reaction is a process that leads to the separation of chemical substances.

• A chemical reaction is a process that leads to the formation of new elements.

What are energy changes in reactions?

• Energy changes in reactions are caused by temperature changes

• Difference in energy between reactants and products

• Energy changes in reactions are caused by changes in concentration

• Energy changes in reactions are caused by changes in pressure

Give an example of a physical change.

• Boiling water

• Burning wood

• Melting ice

• Mixing salt and water

Give an example of a chemical change.

• Mixing of salt and water

• Melting of ice

• Burning of wood

• Cutting a piece of paper

What are some physical properties of matter?

• Weight, size, shape, temperature

• Mass, volume, density, color, texture

• Taste, smell, sound, hardness

• Length, width, height, transparency

What happens during a chemical reaction?

• Atoms remain unchanged during a chemical reaction.

• Atoms break apart to form new substances.

• Atoms rearrange to form new substances.

• Atoms combine to form new substances.

What are some energy changes that can occur in reactions?

• heat transfer, light emission, electrical energy transfer, and chemical potential energy conversion

• sound production, kinetic energy transfer, gravitational potential energy conversion, and nuclear energy transfer

What are some examples of physical changes?

• Burning wood, rusting metal, evaporating water

• Chopping wood, breaking glass, grinding coffee beans

• Mixing salt and water, dissolving sugar in coffee, crushing a can

• Melting ice, boiling water, tearing paper

What are some examples of chemical changes?

• boiling water, freezing water, melting ice

• mixing salt and water, dissolving sugar in water, crushing a can

• burning wood, rusting of iron, cooking food, and digesting food

• cutting paper, breaking a glass, tearing a cloth