A hydrophilic substance has an affinity for water. Contrary to popular belief, a molecule does not have to dissolve in water to be considered hydrophilic (although most do) which is shown in colloids and cotton. Salt is an example of a hydrophilic substance. Hydrophilic molecules are polar and capable of hydrogen bonding, which allows it to dissolve in water. The positively charged sodium and negatively charged chloride are attracted to oxygen and hydrogen in water. Another example of a hydrophilic molecule is sucrose.