1. the following is true about a unit cell and a crystal. |
2. Which of these best describe a unit cell |
3. The volume of the FCC unit cell is |
4. Find the atomic packing factor (APF) for FCC |
5. Calculate the volume percentage change as iron transform from bcc to FCC if the atomic radii are 1.240A and 1.270A respectively |
6. Find the index of a plane that intercepts the three axes at unit cell distant 1, 1 and ½ a) |
7. The valency of calcium of atomic number 20 is |
8. Which of these statement is false |
9. If the molar mass for Iron(Fe) carbon is 55.845 g/mole . Find the weight of its unit cell if it has Fcc structure
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10. If for a certain BCC crystal, the (110) plane has a separation of 1.181A and wavelength of X-ray is 1.540A. The glance angle for the 1st line of reflection and the atomic radius will be |
11. Bragg’s law is not a sufficient condition for diffraction by crystalline solids. |
12. Which of these have a Crystal structure not common to metals |
13. X-ray diffraction patterns are used for studying crystal structure of solids because |
14. Which of the following lattices has the highest void fraction? |
15. Graphite is a common allotrope of Carbon. Its crystal structure is: |
16. In which of the following Bravais lattices none of the sides are equal? |
17. Coordination number for an ideal BCC metallic crystal is: |
18. n which of the following Bravais lattices, not all axial angles are right angles? |
19. Which of the following Bravais lattices exist as face centered unit cell? |
20. Most Bravais lattices are of the type: |
21. Grain boundaries are one of the causes of corrosion of metals? |
22. The smallest portion of a crystal which when repeated in different directions generates the entire crystal is called |
23. HCP and BCC are called close-packed structures. Close packed structures have: |
24. Packing efficiency of a crystal structure is the ratio of: |
25. Co-ordination number of a crystalline solid is: |
26. Allotropes differ in which of the following properties: |
27. How many periods are there in a modern periodic table? |
28. Which if the following is not an SI unit? |
29. Elements in the same column of the periodic table have |
30. Which of the following is not a pure form of matter? |
31. Which of the following has the least number of atoms? |
32. Atomic number of a species is the number of: |
33. A first solid phase results in a second solid phase another third solid phase on cooling during __________ reaction. |
34. The phase above eutectoid temperature for 0.8%carbon steels is known as _______ |
35. What is the eutectoid structure of Iron? |
36. What is the maximum %C by weight in hypo-eutectoid steels? |
37. For a FCC lattice structure a= |
38. The electronic configuration of Calcium of atomic number 20 is: |
39. For a BCC lattice atomic packing factor is |
40. State Bragg’s law |
41. If the first line diffraction for the d111 of copper of an FCC crystalline structure is 43degrees. What is the lattice constant a, of copper if the wavelength of the x-rays used is 1.54A |
42. Multiple crystal structures of an element is referred to us |
43. An element with atomic number 18 has a valency of |
44. A compound exhibitting multiple crystal structure is |
45. The index of a plane that intercepts the three axes at a unit cell distance (3,2,1) |
46. Corrosion of metals involves |
47. Difficult to monitor and very dangerous form of corrosion |
48. This form of corrosion occurs due to concentration difference in a component |
49. Which of the following can be used for cathodic protection: |
50. Substitution solid solution involves |