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Chemistry
Chemistry
Problem
An excited He
+
^{+}
+
ion (
Z
=
2
Z=2
Z
=
2
) de-excites from
n
=
3
n=3
n
=
3
to
n
=
1
n=1
n
=
1
in two steps: first
n
=
3
→
2
n=3\rightarrow2
n
=
3
→
2
, then
n
=
2
→
1
n=2\rightarrow1
n
=
2
→
1
. What is the ratio of the wavelengths
λ
32
/
λ
21
\lambda_{32}/\lambda_{21}
λ
32
/
λ
21
of the two photons emitted (take each as a positive quantity)? a)
1.67
1.67
1.67
b)
5.4
5.4
5.4
c)
0.19
0.19
0.19
d)
2.4
2.4
2.4
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