Science / Geology / Expansive Clay (Expansive Soil): A clay soil that expands when water is added and contracts when it dries out. This volume change when in contact with buildings, roadways, or underground utilities can cause severe damage. MORE
Business / Agriculture / Clayton Act: A 1914 law that supplemented the Sherman Anti-Trust Act of 1890 by clarifying market activities (including those in agriculture) considered to be monopolistic or trade-restraining. The Capper-Volstead MORE
Entertainment / Photography / Clayden Effect: Desensitizing of an emulsion by means of exposure to a strong, brief flash of light. MORE
Lifestyle / Painting / Pencil: Graphite wooden jacketed pencils as are known today date from the end of the 17th century when there was a prosperous British business in the north country and when, as Sir John Pettus commented, 'Bla MORE
Science / Periodic Table of Elements / Potassium (K): Atomic number: 19, Atomic mass: 39.0983 g.mol -1, Electronegativity: 0.8, Density: 0.86 g.cm -3 at 0 ?°C, Melting point: 63.2 ?°C, Boiling point: 760 ?°C, Vanderwaals radius: 0.235 nm, Ionic radius MORE
Science / Periodic Table of Elements / Fluorine (F): Atomic number: 9, Atomic mass: 18.998403 g.mol -1, Electronegativity: 4, Density: 1.8*10-3 g.cm-3 at 20?°C, Melting point: -219.6 ?°C, Boiling point: -188 ?°C, Vanderwaals radius: 0.135 nm, Ionic r MORE