John Gough (natural philosopher) wife and seven of their children. He was buried in the parish churchyard of Kendal. Gough had wide-ranging scientific interests. He published papers in natural history, mechanics, mathematics, chemistry, and experimental physics. One of his most interesting pieces of work was an investigation into the properties of natural rubber or Caoutchouc. He was the first to describe the heat released when a rubber band is quickly stretched, the heat being detected by the lips to which the band is pressed. When stretched rubber is heated, it contracts, a reversal of the normal behaviour of materials when heated. Gough published these
Amount of substance are atoms in of the isotope carbon-12. This number is called the Avogadro number and has the value It is the numerical value of the Avogadro constant, which has the unit mol, and relates the molar mass of an amount of substance to its mass. Therefore, the amount of substance of a sample is calculated as the sample mass divided by the molar mass of the substance. Amount of substance appears in thermodynamic relations such as the ideal gas law, and in stoichiometric relations between reacting molecules as in the law of multiple proportions. Another unit of amount of substance