SUMMARY / RELATED TOPICS

Separatory funnel

A separatory funnel known as a separation funnel, separating funnel, or colloquially sep funnel, is a piece of laboratory glassware used in liquid-liquid extractions to separate the components of a mixture into two immiscible solvent phases of different densities. One of the phases will be aqueous, the other a lipophilic organic solvent such as ether, MTBE, chloroform, or ethyl acetate. All of these solvents form a clear delineation between the two liquids; the more dense liquid the aqueous phase unless the organic phase is halogenated and can be drained out through a valve away from the less dense liquid, which remains in the separatory funnel. A separating funnel takes the shape of a cone with a hemispherical end, it has a stopper at the stopcock, at the bottom. Separating funnels used in laboratories are made from borosilicate glass and their stopcocks are made from glass or PTFE. Typical sizes are between 30 mL and 3 L. In industrial chemistry they can be much larger and for much larger volumes centrifuges are used.

The sloping sides are designed to facilitate the identification of the layers. The stopcock-controlled outlet is designed to drain the liquid out of the funnel. On top of the funnel there is a standard taper joint which fits with a ground glass or Teflon stopper. To use a separatory funnel, the two phases and the mixture to be separated in solution are added through the top with the stopcock at the bottom closed; the funnel is closed and shaken by inverting the funnel multiple times. The funnel is inverted and the tap opened to release excess vapor pressure; the separating funnel is set aside to allow for the complete separation of the phases. The top and the bottom tap are opened and the lower phase is released by gravitation; the top must be opened while releasing the lower phase to allow pressure equalization between the inside of the funnel and the atmosphere. When the bottom layer has been removed, the stopcock is closed and the upper layer is poured out through the top into another container.

The separatory funnel relies on the concept of "like dissolves like", which describes the ability of polar solvents to dissolve polar solutes and non-polar solvents to dissolve non-polar solutes. When the separatory funnel is agitated, each solute migrates to the solvent in which it is more soluble; the solvents do not form a unified solution together because they are immiscible. When the funnel is kept stationary after agitation, the liquids form distinct physical layers - lower density liquids will stay above higher density liquids. A mixture of solutes is thus separated into two physically separate solutions, each enriched in different solutes; the valve may be opened after the two phases separate to allow the bottom layer to escape the separator funnel. The top layer may be retained in the separatory funnel for further extractions with additional batches of solvent or drained out into a separate vessel for other uses. If it is desired to retain the bottom layer in the separatory funnel for further extractions, both layers are taken out separately, the former bottom layer is returned to the separatory funnel.

Each independent solution can be extracted again with additional batches of solvent, used for other physical or chemical processes. If the goal was to separate a soluble material from mixture, the solution containing that desired product can sometimes be evaporated to leave behind the purified solute. For this reason, it is a practical benefit to use volatile solvents for extracting the desired material from the mixture. One of the drawbacks of using a separatory funnel is emulsions can form and can take a long time to separate once formed, they are formed while liquids are being mixed in the separatory funnel. This can occur. If an emulsion is formed, one technique used to separate the liquids is to swirl the solution in the separatory funnel. If the emulsion is not separated by this process, a small amount of saturated saline solution is added. Research is being done on alternative, more efficient techniques utilizing stir bars to decrease or eliminate the chance of emulsification, thus decreasing the amount of waiting time.

The largest risk when using a separatory funnel is that of pressure build-up. Pressure accumulates during mixing if a gas evolving physical change occurs; this problem can be handled by opening the stopper at the top of the funnel while mixing. This should be done with the top of the funnel pointed away from the body. Decantation is a process of pouring off the top layer of liquid from a bottom layer of liquid or solid Decanter centrifuge Dropping funnels are similar in shape and design, may be used as separatory funnels, they have standard taper ground glass joints at the stem. Partition coefficient is a measure of the distribution of an analyte between the two phases in a separation

Borisoglebsky (inhabited locality)

Borisoglebsky, Borisoglebskaya, or Borisoglebskoye is the name of several inhabited localities in Russia. Urban localitiesBorisoglebsky, Yaroslavl Oblast, a work settlement in Borisoglebsky District of Yaroslavl OblastRural localitiesBorisoglebsky, Murmansk Oblast, an inhabited locality in Pechengsky District of Murmansk Oblast Borisoglebskoye, Kemerovo Oblast, a selo in Novovostochnaya Rural Territory of Tyazhinsky District in Kemerovo Oblast. Постановление №133-а от 8 апреля 2014 г. «Об утверждении реестра населённых пунктов Костромской области». Вступил в силу 11 апреля 2014 г. Опубликован: "СП — нормативные документы", №15, 11 апреля 2014 г.. Губернатор Костромской области. Постановление №586 от 6 октября 2004 г. «Об исключении из учётных данных некоторых населённых пунктов Костромской области». Вступил в силу со дня подписания.. Губернатор Костромской области. Постановление №359 от 17 августа 2007 г. «О признании утратившими силу некоторых Постановлений Губернатора Костромской области». Вступил в силу со дня официального опубликования.

Опубликован: "СП – нормативные документы", #43, 29 августа 2007 г

Senior Deputy Speaker of the House of Lords

The Senior Deputy Speaker is an officer of the House of Lords whose main role is to preside over the House when it is in committee, either in the Lords Chamber or in Grand Committee, when committee stage is taken away from the floor to free up debating time in the main Chamber. The Senior Deputy Speaker deputises for the Lord Speaker, like the Lord Speaker withdraws from political party membership. Additionally, the Senior Deputy Speaker chairs various select committees of the House, has a role in the administration of the House; the current incumbent, Lord McFall of Alcluith, took the office on 1 September 2016. Up until September 2016 the position was known as Chairman of Committees; the Senior Deputy Speaker is assisted by the Principal Deputy Chairman of Committees and a panel of Deputy Chairmen of Committees. The Principal Deputy Chairman is Earl of Kinnoull. In addition to taking the chair in Committee of the Whole House and Grand Committee, Deputy Chairmen are appointed from time-to-time to serve with the Chairman of Committees on unopposed bill committees, which scrutinise private bills against which no petitions have been lodged.

Deputy Chairmen are, by practice, Deputy Speakers. As of 5 March 2018, the panel of Deputy Chairmen are: The Earl of Clarendon, 1715–1723 The Lord De La Warr, 1724–1733 The Earl of Warwick, 1733–1759 The Lord Willoughby of Parham, 1759–1765 The Lord Delamer, 1765–1770 The Viscount Wentworth, 1770–1774 The Lord Boston, 1774–1775 The Lord Scarsdale, 1775–1789 The Lord Cathcart, 1789–1794 The Lord Walsingham, 1794–1814 The Earl of Shaftesbury, 1814–1851 The Lord Redesdale, 1851–1886 The Duke of Buckingham and Chandos, 1886–1889 The Earl of Morley, 1889–1905 The 4th Earl of Onslow, 1905–1911 The Earl of Donoughmore, 1911–1931 The 5th Earl of Onslow, 1931–1944 The Lord Stanmore, 1944–1946 The Earl of Drogheda, 1946–1957 The Lord Merthyr, 1957–1965 The Earl of Listowel, 1965–1976 The Lord Aberdare, 1976–1992 The Lord Ampthill, 1992–1994 The Lord Boston of Faversham, 1994–2000 The Lord MacKay of Ardbrecknish, 2000–2001 The Lord Tordoff, 2001–2002 The Lord Brabazon of Tara, 2002–2012 The Lord Sewel, 2012–2015 The Lord Laming, 2015–2016 The Lord McFall of Alcluith, 2016–present List of committees of the United Kingdom Parliament