Answer:
For pH= 4.00 :
Add 0.1 ml of 0.1 molar NaOH to 50 ml of 0.1 molar potassium hydrogen phthalate .
Semi-conductor,brittle not malleable or ductile.
λ=Wavelength = .129 m = 0.129 m
E = energy = ?
h =Planck constant = 6.63 × 10^-34 J.s
f = frequency of photo/ electromagnetic radiation = c/λ
c = Speed of light in a vacuum = 3 × 10^8 m/s
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I hope I helped you^_^