Abstract: In a process, according to the invention hydridic silanes such as H.sub.2 SiCl.sub.2 or SiH.sub.4 and oligomeric hydridic silanes containing up to 5 silicon atoms are admixed with a hydrocarbon stabilizer. The hydrocarbon may have functional groups selected from among carboxylic ester, aldehyde, keto, ether, thioether, tertiary amino, epoxy and cyano groups and halogen atoms.

Abstract: A process for the preparation of an organohalosilane of the general formula:X.sub.4-n SiR.sub.nin which,R represents a methyl, ethyl, n-propylisopropyl, n-butyl, isobutyl, phenyl or a tolyl functional group;X represents chlorine or bromine; andn is 1, 2 or 3,is disclosed. The process takes place by reacting an SiO.sub.2 -containing material with a hydrocarbon halide of the general formula RX, in which R and X are defined as above. The reaction between the SiO.sub.2 -containing material and RX takes place in the presence of iron powder and either: (a) carbon and a catalyst, in which the SiO.sub.2 -containing material, the iron powder, the carbon and the catalyst are subjected to a heat treatment at 800.degree. to 1400.degree. C. prior to the reaction with RX or (b) an aluminum trihalide and/or boron trihalide in which the halogen is either chlorine or bromine. Alternative (b) may be carried out in the presence of a catalyst.