20mL of water sample is placed into a 55mL PTFE tube with 2.5mL nitric acid, and subject to the following program: Microwave unit heat sample to 160+/4C in 10min and then, for the second stage, to permit a slow rise to 170C for 10min. The system is cooled to room temperature and the content in the vessel is analysed by FAAS. NB; the volume of the content in the vessel before and after microwave program is 100% recovery. Design an experiment for the following; - Calibration - 1) Calculate the required amount of salt to prepare 500mL of 1000mg/L. 2) How to prepare working standards 1,3&5mg/L using the 1000mg/L standard and 100mL volumetric flasks. 3) Calculate the dilution factor for each step. - Fortified Matrix. 1) How to prepare LFM of 1mg/L after taking 5mL from parent sample and transfer to a 50mL volumetric flask. 2) How to prepare LFB of 1mg/L. Laboratory Activity 1) Use the lowest standard to optimize the instrument and record the absorbance Output: calculate the characteristic concentration. 2) Calibrate the Instrument, analyse the sample and quality control samples. Output: Record the characteristic concentration, regression plot, equation of the line, and assess results