ANS:B - 6

The C/H ratio (by weight) of naphtha used in nitrogenous fertilizer making is approximately 6. Naphtha is a hydrocarbon mixture primarily composed of hydrogen (H) and carbon (C) atoms. The C/H ratio indicates the number of carbon atoms per hydrogen atom in the compound. Given that naphtha is a mixture of hydrocarbons, its exact composition can vary, but a typical C/H ratio for naphtha used in industrial processes, including nitrogenous fertilizer production, is around 6.