<em>The substance that can break easily from the list of substances is the </em><em>iodine</em><em>.</em>
<u>Iodine exists as a molecular solid and hence, the molecules are held together by weak Van Der Waal's forces. Iodine thus has characteristic properties of typical molecular solids which include being able to be broken into pieces easily (brittle), low melting and boiling points, insolubility in water, among other properties.</u>
The characteristics of iodine are unlike sodium, calcium, and copper that exist as metal which is hard, tough with high tensile strengths.
