Answer :
(a) The energy of blue light (in eV) is 2.77 eV
(b) The wavelength of blue light is 
Explanation:
The relation between the energy and frequency is:

where,
h = Plank's constant = 
Given :
Frequency = 
Conversion used :

So,


Also,

So,


The energy of blue light (in eV) is 2.77 eV
The relation between frequency and wavelength is shown below as:

Where,
c = the speed of light = 
Frequency = 
So, Wavelength is:


Conversion used : 
The wavelength of blue light is 
Answer:
The answer is 5.10
Explanation:
<h3><u>Given</u>;</h3>
<h3>
<u>To </u><u>Find</u>;</h3>
We know that
pH + pOH = 7
pOH = 7 – pH
pOH = 7 – 1.90
pOH = 5.10
Thus, The pOH of the solution is 5.10
Answer:
three valence electrons
Explanation:
Gallium has three electrons in the outer energy level and therefore has three valence electrons. The identification of valence electrons is vital because the chemical behavior of an element is determined primarily by the arrangement of the electrons in the valence shell.