Coal Tar. Tar derived from both coal and wood (e.g., juniper, pine) are both used for medicinal purposes. However, coal tar is the type used most commonly to treat psoriasis. Tar can help slow the rapid growth of skin cells and restore the skin's appearance. In addition, it can help reduce the inflammation, itching and scaling of psoriasis. Tar products can vary dramatically from brand to brand.
Quick Answer. The lightest element on the periodic table is hydrogen. The atomic weight of hydrogen is 1.00794 and the atomic number is 1. Hydrogen is the most abundant element on the periodic table with 75 percent of the mass of the universe consisting of hydrogen. Continue Reading.
Hydrogen: the essentials. Note that while hydrogen is normally shown at the top of the Group 1 elements in the periodic table, the term alkaline metal refers to the Group 1 elements from lithium downwards and not hydrogen. Hydrogen is the lightest element. It is by far the most abundant element in the universe and makes up about about 90% of the universe by weight. It is also the most abundant element in the earth's sun. Hydrogen as water (H 2 O) is absolutely essential to life and it is present in all organic compounds.