The chemical element's atomic radius is measured by the size of its atoms, usually the medium or typical distance between the central nucleus and the surrounding electron shells. As the limit is not a well defined physical entity, different definitions of non-equivalent atomic radius exist.
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D is the answer cause two h20 + o2(g)
Co2 = two covalent bonds
ccl4 = 4 covalent bonds
Lih = covalent bond
