Answer: Fireworks exploding is a chemical change.
Explanation: Lighting gunpowder, and making the explosion is a chemical change.
My sample would be 4000 years old because on my graph, I had about 9 Virtualium left at trial 4 so I am guessing that it would be 4000 years old.
Battery represents a simple machine
Answer:
Explanation:
17. it goes from solid copper to aqueous copper:
Cu(s) --> Cu₂(aq) + 2e⁻
18. complete ionic:
Cu(s) --> Cu₂(aq) + 2e⁻
19. net ionic, must include only reacting species, so
Cu(s) --> Cu₂(aq) + 2e⁻
20. this type of reaction is dissolution reaction(redox reaction)
copper reduced from Cu²⁺ to Cu.
Answer:
Aluminum had more value than gold in the 1820s, because it was harder to obtain. Hope this helped :)
