A bond in which the electronegativity difference between the atoms is between 0.5 and 2.0 is called a polar covalent bond. A polar covalent bond is a covalent bond in which the atoms have an unequal attraction for electrons and so the sharing is unequal.
In warm sugar water the yeast will grow and continue to feed on the sugar until it is all gone and as it does this it'll create waste products that are used both in beer and bread.
