Cigarette ashes

RUB A LUMP OF SUGAR WITH CIGARETTE ASHES (TO ACT AS CATALYST). IGNITE. DIP TEST TUBE IN LIME WATER. HOLD OVER BURNING SUGAR. FILM OF CALCIUM CARBONATE SHOWS CO, IN FLAME—PROVING THAT THERE IS CARBON IN SUGAR. 

A sugar cube will not burn on its own, but if some cigarette ash is sprinkled over it, it... 

Ish was experimentally well known for her ability to coax more-or-less pure crystals of a new substance from tiny amounts of solution of an unlikely looking, gluey reaction product. It was rumoured that her success was the beneficiary of traces of her cigarette ash that provided nuclei in the crystallization test tube to help initiate the crystallization process aided by temperature changes and by scratching the side of the tube with a glass rod.25... 

Although your chosen person might get the sugar cube to melt or caramelize he or she will be out of luck when it comes to the cube going up in flames. You come to the rescue with a new sugar cube. Before you place the cube in the tongs dust it on all sides with cigarette ashes. ... 

Perhaps the simplest test method for the evaluation of antistatic finishes is the ash test. A piece of the fabric to be evalnated is mbbed briskly on a piece of plastic or rubber (the vinyl covered arms of a chair, for example). The fabric is then placed over an ashtray containing cigarette ash. The amount of ash transferred to the fabric is an indication of the amount of static charge imparted to the fabric. Owing to the difficulty in quantifying the results, this test is mainly nsed as a qualitative tool to distinguish between antistatic-treated and untreated fabrics. 

Inhalation is the most common route of exposure. Dibenzofuran is present in cigarette ash and is a byproduct of processes in the pharmaceutical industry. When heated to decompose, it emits acrid smoke and irritating fumes. Exposure can also occur by ingestion of contaminated food. 

When heated, a sugar cube (sucrose, melting point 185°C) melts but does not burn. A sugar cube rubbed in cigarette ash burns before it melts. The cigarette ash contains trace amounts of metal compounds that catalyze the combustion of sugar. 

Iskander FY 1986. Cigarette ash as a possible source of environmental contamination. Environ Pollut SerB 11 291-301. 

Perhaps this explains the well known trick that a lump of sugar can be made to burn by previously dipping it in cigarette ash. 

Sogor, C., A. Gaspar, and J. Posta Flame atomic absorption spectrometric determination of total chromium and Cr(VI) in cigarette ash and smoke using flow injection/hydraulic high-pressure sample introduction Microchemical J. 58 (1998) 251-255. 

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