Hello Mate!Well, there are
many definitions and descriptions of isolated systems, and
here are some of them:
1.
It can be a physical system which is located very very far from all other systems, so there is absolutely no interaction between them, thus making it isolated.
2.
It can be a thermodynamic system with rigid walls, which prevents mass and energy to pass through.
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F.
it's the greatest electron "hogger"
as you get closet to it, the stronger the electro negitivity.
He is halogen : they don't like to gain electrons. they are already stable.
Fr and Rn
are metals as far is I can remember. they would prefer losing electrons.
Calculations in chemistry can range from large numbers to the smallest number in decimals to be more accurate in data results. When this occurs using scientific notations allows you to note down results regardless of size as accurate as possible without writing a lot of numbers.
I think the correct answer among the choices listed above is option A. <span>Given a chemical reaction, methane (CH4) burns in oxygen (O2) to produce carbon dioxide (CO2) and water (H2O). The chemical reaction is best represented as:
</span><span>CH4 + O2 ----> CO2 + H2O</span>