I need help on either question you can answer. Thank you god bless
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1.Atomic Number (Z) = Mass Number (A) - Number of Neutrons
neutrons = mass number-atomic number
Atomic mass Cl-37= 17
Mass number Cl-37=37
Neutrons = 37-17=20
2. Mass atom X = mass isotope 1 . % + mass isotope 2.%...
[tex]\tt atomic~mass~X=0.0224\times 88+0.7832\times 90+0.1944\times 91=90.1[/tex]
3. The energy in one photon can be formulated as
[tex]\large{\boxed{\bold{E\:=\:h\:.\:f}}}[/tex]
f = c / λ, so :
[tex]\tt E\approx f\approx \dfrac{1}{\lambda}[/tex]
Energy is directly proportional to frequency and inversely proportional to the wavelength
So, as the frequency of photon increases, the energy of photon increases
4. Based on answer number 3 :
A. The wavelength becomes longer, and the energy decreases