Can someone help me with the with calculating the Average Diffusion Rate

Question

Calculate the Average diffusion rate from time zero for the different time at which you measured. Assume the diameter at time zero to be equal to zero. The formula is

 

Rate[mm/h]= (diameter[mm]/time[min])x60[min]

 

Measurements

 

1min 2 crystals 7 mm 4 crystals 9mm 6 crystals 10 mm

6min 2 crystals 13mm 4 crystals 17mm 6 crystals 21mm

12min 2 crystals 18mm 4 crystals 22mm 6 crystals 25mm

18min 2 crystals 20mm 4 crystals 25mm 6 crystals 29mm

24min 2  crystals 22mm 4 crystals 27mm 6 crystals 31mm

30min 2 crystals 23mm 4 crystals 29mm 6 crystals 33mm

 

I am horrible at math formulas and I am not sure how to work this can someone please show me an example of how to do this formula so I can plot my graph

 

 

Answer 1

I'm not exactly sure what you're trying to graph.  Are you going to have 3 graphs? One for the 2 crystals data, one for the 4 crystals data, and one for the 6 crystals data?  If so, then the function for the 2 crystal data will have the following points 

 

R(1) = (7mm/1min)*60min/h = 420 mm/h

R(6) = (13mm/6min)*60min/h = 130 mm/h

R(12) = (18mm/12min)*60min/h = 90 mm/h

R(18) = (20mm/18min)*60min/h = 66.7 mm/h

R(24) = (22mm/24min)*60min/h = 55 mm/h

R(30) = (23mm/30min)*60min/h = 46 mm/h 

 

Put Time in minutes from 0 to 30 on the x-axis and R in mm/h from 0 to 500 or so on the y-axis and then draw a smooth curve thru the points 

 

(1,420), (6,130), (12,90), (18,66.7), (24,55) and (30,46) 

 

Then do the same thing for the 4 crystals and 6 crystals cases