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Checking Charge After a Crystal Substitution 4 questions
Checking Charge After a Crystal Substitution
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A ceramic model begins with six metal ions M2+ and six oxide ions O2-. The display replaces two of the M2+ ions with two Li+ ions in their sites. The model then adjusts the ion counts to restore zero total charge.
| State | M2+ ions | Li+ ions | O2- ions |
|---|---|---|---|
| Start | 6 | 0 | 6 |
| After replacement only | 4 | 2 | 6 |
Question 1
What total charge does the model have just after replacement?
- −4
- −2
- 0
- +2
Question 2
Find the number of oxide ions that could remain if removing oxide is the only way to restore zero charge.
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A second compensation model leaves all six oxide ions in place and adds one M2+ ion at a new site. Both models can restore zero total charge.
Question 3
A structural reading shows five oxide ions. Use the models to identify which change it supports.
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Question 4
State the final M²⁺ and oxide counts in each neutral model. Explain why the same net charge does not distinguish the models.
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