ELECTRIC FURNACE FOR CALCIUM CARBIDE PREPARATION WILLIAM B. SANFORD
Savona Central School, Savona, New York TWO students in my chemistry class wished to prepare calcium carbide. To carry out the experiment they constructed an electric furnace. The student drawing clearly explains the construction. They used carbons and a resistance from a health lamp to form the arc. The pit was closed with an asbestos plug, in which was a small hole to permit the escape of carbon monoxide.
They ground and mixed coke with an equal weight of lime. They calculated the weights should be in the ratio of 3 to 5, but later found that better results were obtained by using equal weights of each. The arc passed through the mixture for ten minutes. The carbon monoxide burned a t the opening in the asbestos plug. Very small pieces of calcium carbide had formed. The students removed the pieces from the furnace and allowed them to cool. They placed them in a testtube and added water. The acetylene formed was identified by its odor. The gas was ignited as it bubbled out. The yields were very small but the experiment created a great amount of class interest. At present the students are preparing to use sand and carbon in an attempt to prepare carbornndum.
