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To know how many moles of iron can be recovered from 100 kg of Fe₃O₄ we'll need to use the
molar mass of Fe₃O₄ and apply the conversion factor to go from kg of Fe₃O₄ to moles of Fe in the following way:

So, theoretically, one could recover
1192,68 moles of Fe from 100 kg of Fe₃O₄
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The Correct option is E. Chemical energy to Mechanical energy.
Answer: B. 1:2
Explanation: Beryllium and chlorine forms a binary ionic compound. Ionic compound is formed when a metal loses its electrons to a receiving non metal. Beryllium (metal) has two valence electrons while chlorine (nonmetal) has seven valence electrons, and so a beryllium atom has to give out its two valence electrons to attain a duplet stable structure while a chlorine atom will gain one electron to attain its stable octet structure. In the reaction between beryllium and chlorine, two atoms of chlorine have to accept the two electrons from one beryllium atom to attain their stable octet structure.
The formula of the compound formed is BeCl2.
The size of atom reduces
Electronic configuration of sodium -
2,8,1
In order to become stable it loses one electron and becomes positive ion.
It's size reduces.