Corrosive substance or slowly over days or years, e.g. the rusting of iron in a bridge. Sometimes the word caustic is used as a synonym for "corrosive", but "caustic" refers only to strong bases, particularly alkalis, and not to acids, oxidizers, or other non-alkaline corrosives. At low concentrations, a corrosive substance is called an irritant, and its effect on living tissue is called irritation. At high concentrations, a corrosive substance causes a chemical burn, a distinct type of tissue damage. Corrosives are different from poisons in that corrosives are immediately dangerous to the tissues they contact, whereas poisons may have systemic toxic
Magic cube classes Frost referred to all but the simple class as Nasik cubes. <br>The smallest normal diagonal magic cube is order 5. See Diagonal magic cube. Minimum correct summations required = 3"m" + 6"m" + 4 All 4m pantriagonals must sum correctly (that is 4 one-segment, 12("m"-1) two-segment, and 4("m"-2)("m"-1) three-segment). There may be some simple AND/OR pandiagonal magic squares, but not enough to satisfy any other classification. <br>The smallest normal pantriagonal magic cube is order 4. See Pantriagonal magic cube. <br>Minimum correct summations required = 7"m". All pan-"r"-agonals sum correctly for "r" = 1 and 3. A cube of this class