Question

5. The color of the FeSCN2 complex might be appropriately described as "blood-red"; indeed, concentrated solutions of this complex have a color almost identical to that of blood. Considering the composition of this complex, why might that not be surprising? (Hint: what species is responsible for the red color of blood? Again, feel free to use your textbook or the internet.) (10 points/ 6. Determine the energy in joules) of a light (radiation) of 625 nm. [10 points 1 nm = 1 x 10-'m The speed of light = 2.99 x 10 m/s Planck's constant = 6.626 X 104 m² kg/s

Answer 1

5. The species responsible for color of complex will be haemoglobin, which is found in red blood cells. Haemoglobin contains iron in it as complex FeSCN²⁺ also contains iron in it. Therefore it is not surprising that the color of complex will be "blood-red".

6. The formula to calculate energy of light is given by,

E = h$\nu$ = hc / $\lambda$

Where $\lambda$ = 625 nm = 625 * 10^-9 m

Now put the all given values in formula

E = (6.626 * 10^-34 m² kg/s * 2.99 * 10⁸ m/s) / 625 * 10^-9 m

E = (1.9811 * 10^-25 kg m² / s² ) / 625 * 10^-9 = 3.1698 * 10^-19 kg m² /s²

Since 1 J = 1 kg m² /s²

Therefore, E = 3.1698 * 10^-19 J.

Therefore energy of light is 3.17 * 10^-19 J.

If you find any mistake please mention in the comment box.

Thanks.