I think the answer is D in my opinion
A=Mass number=24
N=neutrons=13
Z=atomic number.
A=Z+N
24=Z+13
Z=24-13
Z=11
The atomic number is 11, and this atom is sodium.
Electron transitions from higher to lower energy levels cause emission of energy in the form of electromagnetic waves, each with their own specific wavelength. Because the energy levels of elements are quantized, each transition has a specific energy difference. The collection of these transitions makes up the emission spectrum and each spectrum is unique to a specific element, allowing identification.
As in relative abundance , one is take reference
So,
One is taken as 1:
Other is subtracted from it:
(1 - 0.6011)(atomic mass of Ga-71)
Equation can be written as:
<span>69.723 = (0.6011)(68.9256) + (1-0.6011)x </span>
<span>(1-0.6011) is the percentage abundance of Ga-71 expressed in percentage: </span>
<span>Solving for x </span>
<span>28.2918 = 0.3989 x </span>
<span>x= 70.9246.......</span>