Question

question 17
7 pts
below is a paragraph that tells a story of two people on a camping trip. decide if each situation (underlined below) is a chemical or physical change.
sophia and jorge went camping on the fourth of july to watch the annual fireworks select festival. when they arrived at the campsite sophia collected firewood, which she then cut into smaller pieces select for their fire pit. sophia then lit a match select and soon they had a roaring fire. hungry, jorge took hot dogs out of the cooler. the hot dogs were put on metal rods and cooked until they were dark brown select . not feeling well, they discovered that the cooking rods were rusted select . sophia then dissolved some stomach medicine tablets into her water bottle, which reacted with the water and formed lots of bubbles select . after an hour they felt better, and sophia and jorge decided to sip on some cold pepsi’s. when they were finished they crushed their cans select , threw them in the trash, and watched the fireworks show. all in all it was a great summer day!
desk 1

Explanation:

1. Fireworks: Fireworks involve combustion and the production of new substances (like gases, light, sound), so it's a chemical change.
2. Cut into smaller pieces: Only the size of the firewood changes, no new substance is formed. This is a physical change.
3. Lit a match: Lighting a match involves combustion (chemical reaction with oxygen, new substances formed), so chemical change.
4. Cooked until dark brown: Cooking (especially browning) involves chemical reactions (like Maillard reaction) forming new substances, so chemical change.
5. Rusted: Rusting is the oxidation of iron (forming iron oxide), a new substance, so chemical change.
6. Reacted with water and formed bubbles: The medicine reacting with water to form bubbles means a new substance (gas, maybe) is formed, so chemical change.
7. Crushed their cans: Only the shape of the cans changes, no new substance, so physical change.

Answer:

1. fireworks: Chemical Change
2. cut into smaller pieces: Physical Change
3. lit a match: Chemical Change
4. cooked until they were dark brown: Chemical Change
5. rusted: Chemical Change
6. reacted with the water and formed lots of bubbles: Chemical Change
7. crushed their cans: Physical Change