In IUPAC nomenclature, however, hexane is the unbranched isomer (n-hexane); the other four isomers are named as methylated derivatives of pentane and butane. IUPAC also uses the term as the root of many compounds with a linear six-carbon backbone, such as 2-methylhexane (C7H16), which is also called isoheptane.
Dentin is the substance between enamel or cementum and the pulp chamber. It is secreted by the odontoblasts of the dental pulp. The formation of dentin is known as dentinogenesis. The porous, yellow-hued material is made up of 70% inorganic materials, 20% organic materials, and 10% water by weight.
Rock, Water, Air, and organic matter. One part of soil is rock that has been broken down over time by wind, water, and chemical processes. Another material is called organic matter. It is made up of decaying plant and animal matter. Water and air are the other ingredients in soil. In a good garden soil, about 45 percent will be rock particles, 5 percent organic matter like leaves, 25 percent water, and 25 percent air. erosion is the gradual wearing away and breaking down of rocks and other material through a variety of processes.