PH the Hammett acidity function, "H", has been developed in connection with superacids. The concept of "unified pH scale" has been developed on the basis of the absolute chemical potential of the proton. This model uses the Lewis acid–base definition. This scale applies to liquids, gases and even solids. In 2010, a new "unified absolute pH scale" has been proposed that would allow various pH ranges across different solutions to use a common proton reference standard. Pure water is neutral. When an acid is dissolved in water, the pH will be less than 7 (25 °C). When a base, or alkali,
Alkali Act 1863 Alkali Act 1863 Under the British Alkali Act 1863, an alkali inspector and four subinspectors were appointed to curb discharge into the air of muriatic acid gas (gaseous hydrochloric acid) from Leblanc alkali works. In 1874, under the Alkali Act 1874, the Inspector became the Chief Inspector. The first Chief Inspector was Dr Robert Angus Smith, he was statutorily responsible for the standards set and maintained by the Inspectorate, and reported directly to the Permanent Secretary of his department. For the first sixty years of its existence, the Inspectorate was solely concerned with the heavy chemicals industry, but from the