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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The Earth's core is the part of Earth in the middle of our planet. It has a solid inner coreand a liquid outer core.
Mass=density x volume, i.e. 1.03 x 85.32 = 87.88 g
Answer: 55.56 moles of MgO
Explanation:
1 mole = avogadro number
if 6.21x10^25 atoms then molecules of MgO (equal numbers of Mg and O atoms)
= 0.5*6.21x10^25 = 3.105 molecules of MgO
So moles of MgO = 0.5*6.21*10^25/avogadro number = 55.56