A college chemistry student is stadying the properties of four unknown compounds. W. X. Y, and Z. She has ben infonmed that two of thee are iomic and that the other three are covalent. Of the latter, she has been told that the attractions between the formula nits are dispersion forces in one case, hydrogen bonds in another, and covilent (network) bands in another. She has been asked to determine the type of attractions for each substance in an attempt to do so, she carries out experiments that reveal information about the substances properties. Use this information to answer the questions that follow.