Composed of a single proton and a single electron, hydrogen is the simplest and most abundant element in the universe. It is estimated that 90% of the visible universe is composed of hydrogen. Hydrogen is the raw fuel that most stars 'burn' to produce energy. The same process, known as fusion, is being studied as a possible power source for use on earth. The sun's supply of hydrogen is expected to last another 5 billion years. Hydrogen is a commercially important element.
Eau de toilette is a lightly scented cologne used as a skin freshener. The term toilette/toilet used in this context describes the process of washing and personal grooming. Eau de toilette is also referred to as aromatic waters and has a high alcohol content.
What are Eau De Toilette, Eau De Parfum, etc? These terms refer to the strength of the fragrance, or more specifically, to how much high grade alcohol and/or water has been added to the fragrance oils. Parfum (generally the most concentrated form you can buy) has 15-25% perfume oil dissolved in alcohol. Any mixture with a lower proportion of oil to alcohol is an eau (water). Eau Fraiche (Usually 3% or less perfume oil) Eau de Cologne (2 - 5% perfume oil)