The large exponent means that when R d i then small decreases in R cause large increases in repulsion. If the atomic radius of an Fe atom is 0124 nm calculate the volumes of the FCC and BCC unit cells. Welcome To Learnapchemistry Com Chemistry Classroom Teaching Chemistry Worksheet Template Electron configuration was first conceived under the Bohr model of the atom and it is still common to speak of shells and subshells despite the advances in understanding of the quantum-mechanical nature of electrons. . The mass m 0 introduced above is the reduced mass of the system. In contrast the architecture-engineered CNT is shown to expose graphitic prism planes like 10 1 0 C and 11 2 0 C planes which can provide more active C atoms to contact with Al matrix. Short range repulsion only matters when atoms are in very close. Science Chemistry QA Library a Pure iron has a change in crystal structure from BCC to FCC when heating up abo...