Physical changes happen when you do/mix something that can be reversed. Best example is ripping a paper, you can just tape it back together so it is just an observable thing that changes, which is a physical change. Chemical changes happen when you mix things and they make a new substance and can’t be reversed. The best example of this is the Statue of Liberty, which changed in color due to the chemical change between the oxygen and copper, which created a new substance (rust) which made it green instead of copper.
Sorry for the long answer but hope this helps!
The answer is A because the time wouldn't affect the weather that much depending on the circumstances.
Answer: the correct answer is : too many fish caused an imbalance in the ecosystem, so the food web was affected.
Explanation:
The chemical formula : 3HgBr₂(Mercury(II) bromide)
<h3>Further explanation</h3>
Given
The chemical formulas of Mercury and Bromine
Required
The appropriate chemical formula
Solution
A molecular formula is a formula that shows the number of atomic elements that make up a compound.
The number of molecules is determined by the coefficient in front of the compound
the number of atoms is determined by the subscript after the atom and the coefficient
Three molecules⇒ coefficient = 3
one atom of Mercury ⇒Hg
two atoms of Bromine ⇒ Br₂
The chemical formula : 3HgBr₂