Dichotomous key is a tool <span> - a series of questions and choices </span>that allows the user to determine the identity of items in the natural world, such as trees, wildflowers, mammals, reptiles, rocks, and fish. The first step is observing the whole specimen you want to identify. Observing the habitat in which it is growing,its size and overall shape and some<span> distinguishing features. It is very important to make carefully these observations in order to use the key.</span>
a passage for surplus water from a dam.
1. Physical changes are changes affecting the form of a chemical substance, but not it’s chemical composition.
2. A usually irreversible chemical reaction involving the rearrangement of the atoms of one or more substances.
—— remember a physical change you can see the desperate piece in a mix, such as a salad. A chemical change is when you cannot, like if you mix to salad dressings together, you cannot pick them apart again.—-
3. States that mass in an isolated system is neither created nor destroyed by chemical reactions or physical transformations.
4. ^^^ example after question 2.
5. Chemical - you cannot reverse the change — separate the two salad dressings — physical- you can pick pieces apart — you can remove the tomatoes from the lettuce in a salad.
6. The majority of the log has been turned to ash, therefore making most of it into a gaseous form, which is irreversible and much lighter.
7. All are chemical. Those are all changes you cannot reverse.
8. Once you burn a paper into nothing, you cannot reverse the change and make it into paper again.
9. This would still be a physical change. The pieces are only separated, but the object did not chemically change.
Hope this helped!!
