Passage I

X-ray spectroscopy is a way of analyzing a mineral's composition. When an electron beam is directed onto a mineral, each element in the mineral emits characteristic X-rays having a narrow range of energies. The intensityof all X-rays emitted by the elements is measured. The greater the maximum intensity of the X-rays emitted by an ele­ment, the greater the relative concentration of the element in the mineral.

Figures 1 and 2 show X-ray spectroscopy results for Mineral 1 and Mineral 2, respectively, under identical con­ditions. Energy is given in kiloelectron volts (keV); inten­sity is given in counts per second (sec).

2. According to Figure 2 and additional information provided, what is the order of C, Ca, Mn, and Fe, from the element with the lowest relative concentration in Mineral 2 to the element with the highest relative concentration in Mineral 2 ?

Answer and Explanation

Your Answer is

Correct Answer is G

Explanation

The last sentence of the first paragraph shows that the greater the maximum intensity, the greater the relative concentration. So look at figure 2, arrange the maximum value of the ordinate of each element from small to large, it should be Ca, C, Mn, Fe