Fe3C Cementite HELP PLEASE!!!! Hello... I was wondering if someone would be able to help with the follow question... Cementite: consider cementite. Calculate the amount of carbon in Cementite (1) as atomic % (2) as weight % [atomic weights Fe 56, c 12]. Place cementite on the Fe-C phase diagram; explain the nature of its appearance on the diagram, and comment on the nature and properties of cementite. Cementite is a key part of pearlite- how does it contribute to the structure of pearlite? I totally understand the question apart from the atomic % and the weight %, if someone could help i would be so grateful, thanks.