Write C for chemical change or p for physical change. Give evidence to support your answer.

Answer 1

Certainly! Here’s a list of examples with "C" for chemical changes and "P" for physical changes, along with supporting evidence:

1. Burning Wood - C
   Evidence: When wood burns, it reacts with oxygen to produce ash, smoke, and gases. This changes the chemical composition of the wood, forming new substances.

2. Dissolving Sugar in Water - P
   Evidence: Sugar dissolves to form a sugar solution, but the chemical structure of the sugar remains unchanged. If the water evaporates, the sugar can be recovered in its original form.

3. Rusting of Iron - C
   Evidence: Rusting involves the reaction of iron with oxygen and water to form iron oxide (rust), which is a different substance from metallic iron.

4. Melting Ice - P
   Evidence: Ice melting into water is a physical change. The chemical composition (H2O) remains the same, just in a different state (solid to liquid).

5. Baking a Cake - C
   Evidence: The ingredients undergo a chemical change as they heat, forming new compounds (like carbon dioxide and other products) that are different from the original ingredients.

6. Boiling Water - P
   Evidence: Boiling water results in a phase change from liquid to gas (steam) without altering the chemical composition of H2O.

7. Fermenting Sugar to Alcohol - C
   Evidence: During fermentation, sugar is converted into alcohol and carbon dioxide through a biochemical process, resulting in new substances.

8. Shredding Paper - P
   Evidence: Shredding alters the size and shape of the paper but does not change its chemical composition, which remains as cellulose.

By identifying these changes and providing evidence, one can distinguish between physical and chemical changes in various processes.