One remedy for a deficiency of vitamin B12 for the elderly is a regular injection of this important nutrient. The vitamin B12 injection dose depends on factors such as gender and age.
Hydrogen bonds happen in alcohols. As a matter of fact, any molecule that contains a hydrogen atom attached to an atom of nitrogen or oxygen is capable of such a bond. Ethanol is one such alcohol that features hydrogen bonds. Ammonia is an example of hydrogen bonding. In the case of ammonia, however, the hydrogen bond happens to be relatively weak.
Between water molecules hydrogen bonds are found which are called as intermolecular hydrogen bonding The water molecule has H-O-H, 2 hydrogen and one oxygen present. The O atom is highly electronegative in comparison to the H atom, hence it attracts the electron pair towards itself, making O atom itself partial negatively charged and H atom partial positively charged. So, water is a polar compound. The partially negative charged O atoms, (forms bond) attracts partially positively charged H atom from other molecule, forming hydrogen bond, and water forms intermolecular hydrogen bonding.