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.
With dry drowning, water never reaches the lungs. Instead, breathing in water causes your child's vocal chords to spasm and close up after he's already left the pool, ocean, or lake. That shuts off his airways, making it hard to breathe. Secondary drowning happens a little bit differently.