Lewis acids and bases studied chemical bonding. In 1923, Lewis wrote "An acid substance is one which can employ an electron lone pair from another molecule in completing the stable group of one of its own atoms." The Brønsted–Lowry acid–base theory was published in the same year. The two theories are distinct but complementary. A Lewis base is also a Brønsted–Lowry base, but a Lewis acid doesn't need to be a Brønsted–Lowry acid. The classification into hard and soft acids and bases (HSAB theory) followed in 1963. The strength of Lewis acid-base interactions, as measured by the standard enthalpy of formation of an adduct
2011 Super League season results at Millennium Stadium, as part of Magic Weekend<br> B. All St Helens home games in 2011 to be played at Halton Stadium<br> C. Game to be rescheduled for later date, due to Wigan's involvement in the 2011 World Club Challenge 2011 Super League season results This is a list of the 2011 Super League season results. Super League is the top-flight rugby league competition in the United Kingdom and France. The 2011 season started on 12 February, with the Magic Weekend at the Millennium Stadium in Cardiff, and ended on 8 October with the 2011 Super League Grand Final. The