So for D you have to find energy right
from c you get wavelength Lambda
so on D use this
E = Hc / lambda
c is given 1.5 x 10 ^20
h = 6.624 x 10^-34
and then you get answer for energy
Potassium hydroxide is a strong base and hydrobromic acid is a strong acid. This implies that the pH of the end-point [neutralization] of their titration will be around pH 7. A good indicator for this kind of pH is bromthymol blue. This is because this indicator changes its colour at pH 7.
Answer:
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