How do you draw the calibration curve for estimation of potassium in soil using flame photometry?
You then need to plot about 5 or 6 of these samples onto a graph and then mark the line of best fit (basically the best place where a straight line fits). You can then work out the equation of this line by first finding the gradient (m=y2-y1/x2-x1) and slotting that into y=mx+c (c will most likely be 0). You can then run your potassium sample through and plot the position on the y-axis (whatever technique it measures; absorption etc.) and then draw a straight line to the y=mx+c and then a line down towards the x-axis (concentration).