  We present a detailed numerical study of the electronic properties of
single-layer graphene with resonant ("hydrogen") impurities and vacancies
within a framework of noninteracting tight-binding model on a honeycomb
lattice. The algorithms are based on the numerical solution of the
time-dependent Schr\"{o}dinger equation and applied to calculate the density of
states, \textit{quasieigenstates}, AC and DC conductivities of large samples
containing millions of atoms. Our results give a consistent picture of
evolution of electronic structure and transport properties of functionalized
graphene in a broad range of concentration of impurities (from graphene to
graphane), and show that the formation of impurity band is the main factor
determining electrical and optical properties at intermediate impurity
concentrations, together with a gap opening when approaching the graphane
limit.
