feet; abbreviation: ft; symbol: â² , the prime symbol) is a unit of length in the imperial and US customary systems of measurement. Since 1959, both units have been defined by international agreement as equivalent to 0.3048 meters exactly. In both systems, the foot comprises 12 inches and three feet compose a yard.
Avogadro's law (sometimes referred to as Avogadro's hypothesis or Avogadro's principle) is an experimental gas law relating volume of a gas to the amount of substance of gas present.[1] A modern statement of Avogadro's law is:
Alternative Title: Avogadro constant Avogadroâs number, number of units in one mole of any substance (defined as its molecular weight in grams), equal to 6.022140857 Ã 10 23. The units may be electrons, atoms, ions, or molecules, depending on the nature of the substance and the character of the reaction (if any). See also Avogadroâs law.