Question

2. Calculate the theoretical spectral wavelengths of helium given: Color Relative Intensity AE (10-19 J) 2 (nm) literature/calculated) Red Red Yellow Light Green Dark Green Blue Violet Violet Violet 70 100 1000 100 50 100 70 505 2.814 2.977 3.383 3.963 4.039 4.446 4.937 .015 Show sample calculation:

Answer 1

Color	Relative Intensity	$\Delta$E (10-19 J)	$\lambda$ (nm)
Red	70	2.814	706.4
Red	100	2.977	667.7
Yellow	1000	3.383	587.6
Light Green	100	3.963	501.6
Dark Green	50	4.039	492.2
Blue Violet	100	4.446	447.1
Violet	70	4.937	402.6
Violet	50	5.015	396.4

Sample calculation

For first row (Color : Red, Relative intensity : 70)

$\Delta$E = 2.814 x 10^-19 J

Wavelength, $\lambda$ = (h * c) / $\Delta$ E

where h = Planck's constant = 6.626 x 10^-34 J.s

c = speed of light = 3.0 x 10⁸ m/s

Substituting the values

$\lambda$ = [(6.626 x 10^-34 J.s) * (3.0 x 10⁸ m/s)] / (2.814 x 10^-19 J)

$\lambda$ = 7.064 x 10^-7 m

$\lambda$ = 7.064 x 10^-7 m * (1 x 10⁹ nm / 1 m)

$\lambda$ = 706.4 nm