Landsberger-Walker method

Landsberger-Walker Method.—For ordinary chemical purposes, when it is only desired to decide what multiple of the empirical formula of a compound represents the molecule j where, therefore, an accuracy of 5-10 per cent, is sufficient, the Landsberger method, as modified by Walker and Lumsden, 

Apparatus.—The apparatus (Fig. 48) consists of a boiling flask F, and a graduated tube N, surrounded by the wider 

After having determined the volume of the solution, put the different parts of the apparatus together again, and again pass vapour through the solution, until the liquid drops from the condenser at the same rate as before. Read the thermometer and measure the volume of the liquid as above. Three readings of the temperature and the corresponding volume should, if possible, be made. 

To ensure the uniform ebullition of the solvent in tiie flask F, a fresh piece of porous tile should be placed in the flask each time the apparatus is disconnected and before proceeding to pass the vapour into the solution. 

Solvent Bolling point. K Solvent fioilmg point K 

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