Chapter 05, Problem 5.14 An iron-carbon alloy initially containing 0.201 wt% C is exposed to an oxygen-rich and virtually carbon-free atmosphere at 1190°C. Under these circumstances the carbon diffuses from the alloy and reacts at the surface with the oxygen in the atmosphere; that is, the carbon concentration at the surface position is maintained essentially at 0.0 wt% C. At what position will the carbon concentration be 0.151 wt% after a 7 h treatment? The value of D at 1190°C is 7.9 × 10-10 m2/s.

The concentration of Carbon will be 0.0% near the central surface of the alloy.

Explanation:

Iron makes alloy with carbon to form a compound called cementite i.e., Fe3C. Sometimes they combine to form steel and sometimes cast iron. The combination gives a cubic lattice in which carbon plays an important role as the central position taken by carbon and corner is from iron. At the place, The carbon will take the central surface position.

according to kinetic-molecular theory, the following would not be considered an ideal gas:

a gas at very low volumes, when gas particles are very close together

a gas at very low temperatures, when gas particles have very little kinetic energy a gas

a gas with highly polar molecules that have very strong intermolecular forces

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they both have a y in them