Question

d. alexis sister does not like to ride a dirty bike

1. what happened to javars bike as a result of his not cleaning all the water off of his bike?

a. nothing he still has his bike
b. he dented the fender
c. his bike was stolen
d. his bike began to rust

1. which of these examples is a physical change?

a. a bike rusting
b. folding paper into a paper airplane
c. baking a cake
d. oxygen and water reacting with metal to form rust

Explanation:

• For question 4: When water is not cleaned off a bike (which is usually made of metal), it can lead to rusting. Rusting occurs when metal reacts with oxygen and water.
• For question 5: A physical change is a change in which no new substances are formed. Folding paper into a paper airplane is a physical change as the paper's chemical composition remains the same. Rusting (options a and d) and baking a cake (option c) are chemical changes as new substances are formed.

Answer:

1. d. His bike began to rust
2. b. Folding paper into a paper airplane