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Counting Oxygen Atoms in an Ozone Model 4 questions
Counting Oxygen Atoms in an Ozone Model
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A classroom atmosphere model compares ordinary oxygen, O2, and ozone, O3. An O2 molecule has two atoms on a line. An O3 molecule has three atoms in a bent arrangement. The simulation models the overall rearrangement of oxygen atoms as shown in the equation.
3O2(g) → 2O3(g)
Question 1
Which description correctly compares the molecules before and after the rearrangement?
- O₂ and O₃ contain different elements.
- O₂ is bent, and O₃ is a straight two-atom molecule.
- Both contain only oxygen, but O₃ has a bent three-atom arrangement.
- O₂ and O₃ have the same number of atoms per molecule.
Question 2
Calculate the total number of oxygen atoms represented on each side of the equation. Explain how the coefficients and subscripts work together.
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A sealed simulation starts with 12 O2 molecules. After the rearrangement its meter reports 11 molecules, but it does not identify their shapes. A student proposes two particle drawings for that reading.
| Drawing | O2 molecules | O3 molecules |
|---|---|---|
| U | 9 | 2 |
| V | 10 | 1 |
Question 3
Which proposed drawing can represent the sealed simulation? Compare the number of oxygen atoms in each drawing with the original count.
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Question 4
A second instrument detects two separate bent groups, each with three joined oxygen atoms. Explain how this extra evidence distinguishes the drawings.
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