This section considers some of the chemistry behind the colour of dyes and how the target material, for example a fibre, influences the method of dyeing and the dye used. A dye in solution is coloured because of the selective absorption of certain wavelengths of light by specific bonds in the molecule.
Cannot travel in vaccum. Sound is energy and it causes vibration, which travels in a medium. So imagine molecules transfering the energy (vibration) from source toward a particular direction. In water molecules are more rigid than in gas. So vibration is transferred faster.
Water and The Brain by Dr. Corinne Allen www.brainadvance.org Why is Water So Important for the Brain? The Brain is 85% water. Optimal brain function depends on water and lots of it. Water is what keeps the brain signals going. When the quality of water is compromised the signals are short circuited. Water supports DNA and is the largest single source of energy. The brain has no way to store water and dehydration comes if all the water lost in a day is not replaced and this deficiency is accumulated.