A metallurgical engineer is studying a sample of solid Z that contains iron (Fe)…
CHEMISTRY · Multi-part · AP · Chemistry · Compound Structure and Properties · Compound Structure and Properties
Problem
A metallurgical engineer is studying a sample of solid Z that contains iron (Fe) atoms with small carbon atoms inserted into the lattice. Experimental measurements give the following information.
• Microhardness is significantly greater than that of pure iron.
• The sample remains a good conductor of electricity.
• The density is slightly higher than that of pure iron.
• The sample fractures rather than bends when subjected to a bend test.
Answer the questions that follow.
(a) Identify whether solid Z is best described as a substitutional alloy, an interstitial alloy, or a pure metallic solid. Provide evidence from the observations to support your answer.
(b) Using atomic-level reasoning, explain why the introduction of the second element produces the observed changes in hardness and malleability compared with pure iron.
(c) Predict how the electrical conductivity of solid Z compares with that of pure iron at room temperature and justify your prediction.