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Description: | L.C.E.64. (old departmental catalogue number in aluminium paint). DES after DANIELL,John,Fredrick. 1835 London. England MANU Unsigned. circa 1900 DES after VOLTA,Alessandro,Giuseppe,Anastasio,Count. 1800 Pavia, Italy This is a Daniell gravity or "crowfoot" cell whereby the copper cathode sat in the bottom of a glass container and the zinc, crowfoot shaped anode, was suspended at the top. A copper sulphate solution was then added until the vessel was half filled and then a zinc sulphate solution was carefully poured on top. The zinc solution being less dense floated on the top of the copper solution. The out put of this cell was about 1.1 volts but unlike previous designs this was constant until the elecrolyte became mixed or the anode was exhausted.
Daniell also devised a cell consisting of a copper vessel, which acts as the cathode (positive electrode) and an anode (negative electrode) that is made of zinc. The cathode is bathed in an electrolyte of copper sulphate solution and the anode by a zinc sulphate solution. The two electrolytes are separated by a porous ceramic pot. The zinc anode of this cell has been cast with an annular ring surrounding the orignial Daniell "crowfoot" design, simply to increase the surface area of the anode.
Another type of Daniell cell used to vessels each containing one electrode and an appropriate electrolyte. The two electrolytes were then connected by a salt bridge, an inverted u-shaped tube. These cells were relatively safe to use and gave a modest out put of about 1 volt and were commonly found in domestic equipment until they were replaced by the modern dry cell "battery". | License: | http://www.hmag.gla.ac.uk/spirit/rights/ | Publisher: | Hunterian Museum and Art Gallery, University of Glasgow | Rights holder: | Hunterian Museum and Art Gallery, University of Glasgow | Subjects: | SCIENTIFIC COLLECTION : | Source: | Hunterian Museum | Creator: | Hunterian Museum and Art Gallery, University of Glasgow | Identifier: | http://www.huntsearch.gla.ac.uk/cgi-bin/... | Language: | en-GB | Go to resource |
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