The coordination number for an octahedral site in pure copper is .........
Show Hint
- 4
- 6
- 8
- 12
The Correct Option is B
Solution and Explanation
In crystal structures, the coordination number refers to the number of nearest neighbors surrounding a central atom or ion. For pure copper, which adopts a face-centered cubic (FCC) crystal structure, the coordination number for an octahedral site is 6. This is because, in the FCC structure, each atom is surrounded by six atoms at an equal distance in an octahedral arrangement.
Step 1: Understanding the options
- Option (A): 4 — This is the coordination number for a tetrahedral site, not an octahedral site.
- Option (B): 6 — Correct. In the FCC structure, the coordination number for an octahedral site is 6.
- Option (C): 8 — This corresponds to the coordination number for a cubic site, which is not correct for the octahedral site in FCC copper.
- Option (D): 12 — This is the coordination number for an atom in a close-packed structure, but not for an octahedral site.
Step 2: Conclusion The correct coordination number for an octahedral site in pure copper is 6, making Option B the correct answer.
Top Questions on Metallurgical
- A cylindrical Al alloy billet of 300 mm diameter is hot extruded to produce a cylindrical rod of 75 mm diameter at a constant true strain rate of 10 s$^{-1$. The flow stress of the alloy at the extrusion temperature is given by $\sigma = 10 \, (\dot{\epsilon})^{0.3}$ MPa. Assume the alloy is perfectly plastic and there is no temperature rise during the extrusion process. The ideal plastic work of deformation per unit volume is ............ × 10$^6$ J m$^{-3}$ (rounded off to one decimal place).}
- GATE MT - 2025
- Metallurgical Engineering
- Metallurgical
- Front tension is applied during cold rolling of a thin metal sheet. Which of the following statements is/are TRUE?
- GATE MT - 2025
- Metallurgical Engineering
- Metallurgical
- Match the casting defects in Column I with the characteristic features in Column II. Column I:
P. Misrun
Q. Expansion scab
R. Pin holes
S. Hot tearing
Column II:
1. Penetration of liquid metal behind surface layer of sand moulds
2. Metal solidifies prematurely in the mould and some sections of the casting are not filled
3. Cracking because of restraint to contraction in certain areas during solidification and cooling
4. Evolution of gases during solidification resulting in porosity
- GATE MT - 2025
- Metallurgical Engineering
- Metallurgical
- Which of the following techniques can be used to detect an internal defect in a metal casting?
- GATE MT - 2025
- Metallurgical Engineering
- Metallurgical
- In metal casting, which sprue:runner:gate \emph{area ratio represents a non-pressurized gating system?}
- GATE MT - 2025
- Metallurgical Engineering
- Metallurgical
Questions Asked in GATE MT exam
- If \( P e^x = Q e^{-x} \) for all real values of \( x \), which one of the following statements is true?
Bird : Nest :: Bee : __________
Select the correct option to complete the analogy.- Two consecutive estimates of the root of a function $f(x)$ obtained using the Newton-Raphson method are $x_i = 8.5$ and $x_{i+1 = 13.5$, and the value of the function at $x_i$ is 15. The numerical value of the first derivative of the function evaluated at $x_i$ is ............ (in integer).}
- GATE MT - 2025
- Calculus
- Temperatures at two sides of a 0.4 m thick copper plate are 1000 and 500 °C. Assuming steady state, one-dimensional conductive heat transfer through the wall and ignoring end-effects, the magnitude of the heat flux through the wall is ............... × 10$^5$ W m$^{-2$ (in integer).} Given: Thermal conductivity of copper = 400 W m$^{-1}$ K$^{-1}$
- GATE MT - 2025
- Thermodynamics
- A cylindrical specimen is subjected to plastic deformation in tension up to a uniform elongation of 10\%. The final cross-sectional area of the gage section is found to be 20 mm$^2$. The initial cross-sectional area of the gage section is ............ mm$^2$ (rounded off to an integer).
- GATE MT - 2025
- Material Science