The spacing of a series of lines in the microwave spectrum of AIH is c...
Since,
, where I is the moment of inertia of the rotating molecule.
Therefore,
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The spacing of a series of lines in the microwave spectrum of AIH is c...
Given data:
- Spacing of a series of lines in the microwave spectrum of AIH is constant at 12.604 cm-1.
- We need to find the moment of inertia of the AIH molecule in x 10-47 kg/m2.
Calculations:
- The spacing of lines in the microwave spectrum of a diatomic molecule is given by the expression: ΔE = 2B(J+1), where ΔE is the energy difference between two adjacent lines, B is the rotational constant, and J is the rotational quantum number.
- Here, the spacing is given as 12.604 cm-1, which is equivalent to 0.00012604 m-1.
- Therefore, we have: 0.00012604 = 2B(J+1)
- Solving for B, we get: B = 0.00006302 / (J+1)
- The moment of inertia of a diatomic molecule is given by the expression: I = μr2, where μ is the reduced mass of the molecule and r is the bond length.
- For AIH, we can assume that the hydrogen atom is much lighter than the aluminum atom, so we can approximate the reduced mass as: μ ≈ mH/2, where mH is the mass of a hydrogen atom.
- The bond length of AIH is not given, so we cannot directly calculate the moment of inertia. However, we can use some approximations to estimate its value.
- The bond length of a diatomic molecule can be estimated using the expression: r = (0.529 Å) * (n1 + n2), where n1 and n2 are the principal quantum numbers of the two atoms.
- For AIH, we can assume that the aluminum and hydrogen atoms are in their ground states, so n1 = 1 and n2 = 2.
- Substituting these values, we get: r ≈ 1.587 Å.
- Therefore, we have: I ≈ (mH/2) * (1.587 x 10^-10 m)2
- Simplifying, we get: I ≈ 4.45 x 10^-47 kg/m2.
Answer:
- The moment of inertia of the AIH molecule is approximately 4.45 x 10^-47 kg/m2.