Random electron-density inhomogeneities can arise in a turbulent flow of weakly-ionized gas in the lower atmosphere of the Sun. Using an equation describing the process of inhomogeneity formation, we derived an expression for the spatial spectrum of inhomogeneities. The expression is valid for irregularities with scales restricted to the inertial range of turbulence. Integration of the spectrum over the wave-vector space resulted in the formula allowing one, in the given range of scales, to estimate a mean-square level for the deviation of disturbed electron density from the mean value. According to the formula, under ordinary conditions of a quiet region in the lower solar atmosphere when the magnetic field strength is 0.5 mT, the outer scale of turbulence is of order of a mean granular size of 1000 km, and the rate of turbulent energy dissipation ε ≈ 10⁷ cm²/s³, the deviation of disturbed electron density from the background can be about 5 %.