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Checking Metal Ratios at Different Spots 4 questions
Checking Metal Ratios at Different Spots
Base your answers on the information provided and your knowledge of chemistry. Use the 2025 Chemistry Reference Tables as needed.
A display compares two metal models containing X and Y. Both have the same overall ratio of X atoms to Y atoms. The uniform model mixes X and Y throughout one lattice. The grain model has some regions containing X only and other regions containing Y only. A probe can count atoms in small regions.
| Sample | X and Y in region 1 | X and Y in region 2 | X and Y in the whole sample |
|---|---|---|---|
| P | 5 X, 5 Y | 5 X, 5 Y | 100 X, 100 Y |
| Q | 10 X, 0 Y | 0 X, 10 Y | 100 X, 100 Y |
Question 1
Which local result fits the grain model?
- The two regions of P each contain both elements.
- The two regions of Q contain different individual elements.
- P and Q both contain 100 X atoms overall.
- Both whole samples have the same ratio.
Question 2
A student says the same whole-sample atom ratio establishes the same arrangement. Evaluate the claim using the local records.
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A new probe reading on Q covers both measured regions at once, combining the counts from region 1 and region 2.
Question 3
Predict the combined X and Y counts. Explain why this larger reading can hide the local difference.
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Question 4
Describe a follow-up using small-region readings to test whether the first two readings from P are representative.
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