Product Features of Calcium Carbide
1.  It is called calcium carbide( CaC2). It is a hard lump and the cross section is dark grey or brown.
2.  It is lumpy substance, its surface is a little deep gray, has slight nasty smell.
3.  It can produce acetylene gas when met water, it can burn when meets fire.
4.The acetylene gas mix with air will form explosive gas (explosive range of acetylene gas in the air is 2.3% - 81%).