Question

pregunta 1 (1 punto)
is this a chemical or a physical change?
tearing a piece of paper into 100 tiny pieces.
a physical change
b chemical change
pregunta 2 (1 punto)
is this a chemical or a physical change?
burning a piece of paper in a fire.
a physical change
b chemical change
pregunta 3 (1 punto)
is this a chemical or a physical change?
a reaction occurs, and the products are different from what you started with initially.
a chemical change
b physical change
pregunta 4 (1 punto)
is this a chemical or a physical change?
hammering a nail into a piece of wood.
a physical change
b chemical change

Explanation:

• Pregunta 1: Tearing paper only changes its physical form, not its chemical composition, so it's a physical change.
• Pregunta 2: Burning paper involves a chemical reaction with oxygen, producing new substances like ash and gases, so it's a chemical change.
• Pregunta 3: When products are different from the starting - materials, a chemical reaction has occurred, so it's a chemical change.
• Pregunta 4: Hammering a nail into wood only changes the physical arrangement and does not cause a chemical reaction, so it's a physical change.

Answer:

Pregunta 1: a. Physical change
Pregunta 2: b. Chemical change
Pregunta 3: a. Chemical change
Pregunta 4: a. Physical change