We reviewed relations between a irreversible random sequential adsorption of line segments with diffusional relaxation and the diffusion-limited reaction on a one-dimensional lattice. A line segment of length k adsorbed randomly on the lattice with a adsorption probability p. The adsorbed line segment selected randomly diffuses up to a hopping length l with a probability 1-p. The empty area fraction of the lattice follows a power-law behavior as 1-θ(t)=A(k,1)[(1-p)pt] ^–α(k,l), where θ(t) is the coverage fraction of the line segment on the lattice and the exponent α (k,l) depends on the length of the line segment k and the hopping distance l. The kinetics of empty area fraction of the dimer is equivalent to the diffusion-limited reaction A + A → 0 at long times where A is a chemical reactant. For k ≥ 3, the kinetics of the empty area fraction is not interpreted by the kinetics of the diffusion-limited reaction kA → 0. For k ≥ 3, the model with 1>1 stepping corresponds to reactions where the particle (gaps of size l) hops in a correlated way.