Understanding Physical and Chemical Changes

What happens to a substance during a physical change?

• It becomes a completely new substance.

• Its appearance changes but its identity remains the same.

• It cannot be reversed.

• It loses its original properties entirely.

Which of the following is an example of a chemical change?

• Tearing a piece of paper

• Dissolving sugar in water

• Burning wood to produce smoke and ash

• Melting ice into water

What is a key characteristic of a chemical change?

• It is always reversible.

• It does not involve any energy change.

• It results in the formation of a new substance.

• It only affects the physical state of a substance.

How can you differentiate between a physical and a chemical change?

• A physical change always involves heat.

• A chemical change can be easily reversed.

• A chemical change results in new substances being formed.

• A physical change alters the substance's identity.

Which scenario best illustrates a physical change?

• Burning of paper

• Melting of ice

• Rusting of iron

• Baking a cake