Question #76462
if al3+ replaces na+ ions at the edge center of nacl lattice THEN CALCULATE THE VACANCIES IN 1 MOLE OF NACL
Expert's answer
Answer on Question #76462 - Chemistry - Physical Chemistry
Question:
if al3+ replaces na+ ions at the edge center of nacl lattice THEN CALCULATE THE VACANCIES IN 1 MOLE OF NACL
Solution:
Since there are 1 units of NaCl in each cell, there are 3 Na + ions in the edge centers. So, 1 Al³⁺ will replace 3 Na⁺ ions. 3/4 moles of Na⁺ will replace by 1/4 mol Al³⁺ (for electrically neutral), and the residual Na⁺ ions in the crystal are 1/4 moles. Therefore, in the crystal, 1/2 of the mole of the lattice sites will occupy 1/2 moles (1/4 moles of Al³⁺ + 1/4 moles of Na⁺) cations, so the vacant sites:
1/2 mol = 1/2 * 6.02 * 10²³ = 3.0125 * 10²³.
Answer: 3.0125 * 10²³.
Answer provided by AssignmentExpert.com
Learn more about our help with Assignments: Physical Chemistry
Comments
Dear Ankita Bania, Questions in this section are answered for free. We can't fulfill them all and there is no guarantee of answering certain question but we are doing our best. And if answer is published it means it was attentively checked by experts. You can try it yourself by publishing your question. Although if you have serious assignment that requires large amount of work and hence cannot be done for free you can submit it as assignment and our experts will surely assist you.
I can't understand why did u take 3/4 mol Na+ and how did 1/2 mol remained vacant??