Abstract
It is common practice to use sodium chloride saturated water solution instead of water for determine the acetylene generating rate.
But, practically nothing is known about the influence of sodium chloride on the chemical reaction between calcium carbide and water.
With the object to clear this influence, we executed the repeated acetylene generating tests by carbide dipping in water and sodium chloride saturated water solution and compared its influence.
By precise observations, we recognized that the temperature raising in water is visibly higher than in sodium chloride saturated solution.
Hence, this proves surely that sodium chloride saturated water solution will disturb gas generation.
Accordingly to Author's further research of this phenomenon, the reaction rate from the surface of a carbide lump to centere is lower about 10% than in water.
Retardation of the acetylene generating rate in sodium chloride water solution will be caused by following factors that is ;
(1) Suspended white slime remains fairly longer time than in water.
(2) Bubbles and foams on the gas generated solution surface are relatively stable and these layers are thick in sodium chloride saturated water solution.
In the case of (1) item, for example, 88 weight % of floating slime precipitated in water, but 70 weight % in sodium chloride saturated water solution, its generation will occur in more slush solution state (Fig. 1).
Generated bubbles and foams are unstable in the case of water, therefore, disappears immediately.
This phenomenon will attribute to promote acetylene generation (Fig. 5 (a), (b)).
