Observations when a Physical and Chemical Change Occurs

[Jessica]

1. Describe two observations you might make when a physical change occurs. When a physical change occurs, two observations you might make are a change in color and shape.

2. Describe two observations you might make when a chemical change occurs. When a chemical change occurs, two observations you might make is when the substance turns into a completely different substance and ______________.

Good answers? Are there better ones? Need some help with #2

[sosia]

When a physical change occurs, the nature and propierties are still the same, they are the same substances.(Examples: a folded paper, a breaked glass bottle, melted butter, boilde water)

When a chemical changes occurs, the original ones changes in different ones, with different propierties.(Examples: ashes after wood burning, rust in iron, grape juice in wine)

You have five physical senses: see (color), smell (odor), hearing (sounds different when falls ) , touch (shape), taste (do not try this ).
Typical physical changes: freeze, boil, evaporate, or condense (or broke, it do not change identity)
Typical chemical changes: a given off gas, different color, heat and light emission, a
precipitate.
With this you must do your homework

[Jessica]

Originally Posted by sosia

When a physical change occurs, the nature and propierties are still the same, they are the same substances.(Examples: a folded paper, a broken glass bottle, melted butter, boiled water)

When a chemical changes occurs, the original ones changes in different ones, with different propierties.(Examples: ashes after wood burning, rust in iron, grape juice in wine)

You have five physical senses: see (color), smell (odor), hearing (sounds different when falls ) , touch (shape), taste (do not try this ).
Typical physical changes: freeze, boil, evaporate, or condense (or broke, it do not change identity)
Typical chemical changes: a given off gas, different color, heat and light emission, a
precipitate.
With this you must do your homework

Thanks! I also did a bit of correction

[Jessica]

Wait, you didn't exactly answered #2. What would go in the blank?

[Rusty]

Your task is to list two observations you might make when a chemical change occurs. Sosia gave you several items to choose from, and there are others.
While it is true that there is a change of substance, what two things can you observe while this change is taking place? List them as your answer.

[Jessica]

so can has different properties go in the blank?

[Rusty]

Throw out a change in substance and different properties.

Think about what you can observe (see, hear, smell, touch, taste) when a chemical change occurs and list two such items. When wood burns, is there a smell? What can be seen? What happens if you touch the wood while it is burning? Do you hear anything while the wood is burning? List two of these answers. Those are examples of things you can observe when a chemical change is occurring.

Now, if you take a sheet of copper and heat it up enough to stretch it into thin wire, what observations can be made (using the five senses)? Did the copper change into something else? No, it only changed in shape and size. Those are two observations you can make about a physical change.

Now, if you expose the thin copper wire to the elements long enough to rust, copper no longer exists. Explain how that happened. What two observations could you have made if you were to check on the condition of the wire every day? For one, you would see a change in color, from copper to green, as oxidation occurs. What else?