10g of hydrofluoric acid gas occupies 5.6 litre of volume at STP. If the empirical formula of the gas is HF, then its molecular formula will be (Atomic Mass of F = 19)

10g (HF)n occupy 5.6L at STP Xg (HF)n occupy 22.4L at STPMFW of (HF)n = 40EFW of HF = (1 + 19) = 20 MF of hydrofluoric acid = (HF)2                                  = H2F2