Element 'X' forms a chloride with the formula XCl2, which is a solid with high melting point. X would most likely be in the same group of the periodic table as: I) Si
2) Al
3) Mg
4) Na

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)in the deacon process for the manufacture of chlorine, hcl and o2 react to form cl2 and h2o. sufficient air (21 mole% o2, 79% n2) is fed to provide 35% excess oxygen, and the fractional conversion of hcl is 85%. calculate the mole fractions of the product stream components.