 Acid hydrolysis of calcium monosilicide (CaSi) produces (SiH2)x. CaSi consists of zigzag silicon chain with the formula (Si2−)n. This chain is preserved in the hydrolysis.This reaction was reported in 1921 by the German chemists Lothar Woehler (1870–1952) and Friedrich Mueller.In 1923, German chemists Alfred Stock (1876–1946) and Friedrich Zeidler (1855–1931) found the (SiH)x polymer is formed along with silane gas by the action of sodium amalgam on dichlorosilane (SiH2Cl2).