Which of the following properties is characteristic of typical amorphous network solids?

(select all that apply)
__poor conductor of electricity as a solid
__soft
__good conductor of electricity as a liquid
__noncrystalline
__formed using covalent bonds.
__wide range of melting points possible

The content of manganese (mn) in steel was determined spectrophotometrically and with the use of the standard addition method. an unknown sample of mn from a digested steel sample gave an absorbance of 0.185 when analyzed spectrophotometrically. when 5.00 ml of solution containing 95.5 ppm mn was added to 50.0 ml of the unknown steel solution (digested sample), the absorbance was 0.248. calculate the concentration, in parts-per-million (ppm), of mn in the digested steel sample solution.