The K_ X-rays from certain elements are provided below. Element Ne P Ca Mn Zn Br Energy (keV) 0.858 2.14 4.02 6.51 9.57 13.3 If a Moseley-type plot of versus Z is drawn for the K_ radiation, which of the following best describes the expected shape of the graph?

Step-by-step solution

According to Moseley's law, the frequency of the emitted X-ray is related to the atomic number Z by the equation: = a(Z - b) where a is a proportionality constant and b is the screening constant. For K_ radiation, the transition occurs from the M shell ( n=3 ) to the K shell ( n=1 ). The screening constant b for the K-series is a positive value. The equation represents a straight line when is plotted against Z . At the Z -intercept, = 0 , which gives Z = b . Since b > 0 , the graph is a straight line with a positiv