In karate there are two types of grades they are called kyu grades and dan grades. Kyu means student and refers to a student who is not yet a black belt, ie a colored belt. The kyu number refers to how many grades away from black belt you are. For example 6th kyu means you are 6 grades away from black belt. Most styles have 10 kyu grades but some may have more or less.
Sulfur is the second element in the sixteenth column of the periodic table. It is classified as a nonmetal. Sulfur atoms have 16 electrons and 16 protons with 6 valence electrons in the outer shell. Sulfur is the tenth most abundant element in the universe. Sulfur can take the form of over 30 different allotropes (crystal structures). This is the most allotropes of any element.
Sulfur is a chemical element with an atomic number of 16 and an atomic symbol of S. At room temperature it is a yellow crystalline solid. Even though it is insoluble in water, it is one of the most versatile elements at forming compounds. Sulfur reacts and forms compounds with all elements except gold, iodine, iridium, nitrogen, platinum, tellurium, and the inert gases. Sulfur is abundant and occurs throughout the Universe, but it is rarely found in a pure, uncombined form at Earth's surface. As an element, sulfur is an important constituent of sulfate and sulfide minerals. It occurs in the dissolved ions of many waters. It is an important constituent of many atmospheric, subsurface, and dissolved gases. It is an essential element in all living things and is in the organic molecules of all fossil fuels.