A valuable archeological flint arrowhead is to be examined for nickel as a trace component by ED-XRF (x-ray fluorescence). Flint is a silica material similar to quartz. A blank nickel-free quartz sample yields a signal of 7.8 units of intensity. The arrowhead yields an intensity of 115.6 units. A standard reference materials of nickel in quartz are purchased that has 44.2 micrograms of nickel per g of quartz. This standard material is utilized to yield 78.9 units of XRF intensity under the same conditions.
1. Explain what is the mass percentage of nickel in the arrowhead
2. Comment on any other information which this experiment might yield about this arrowhead
3. Explain what advantage does XRF have in this situation over ICP-AES