25 When calculating the number of selenium hydrosol par

25 When calculating the number of selenium hydrosol par

25 When calculating the number of selenium hydrosol particles at two levels, located at a distance of 100⋅10-6 m, 733 particles were found on the lower level, and 444 at the upper level. The density of selenium is 4.27 g / cm3; water density 1 g / cm3; Experimental temperature T = 292 K. Calculate the average particle diameter of selenium.

Additional information:

If you do not open the file - install the RAR archiver. Inside the archive you will find a solution in Word format.
Questions and problems from the manual:
"Laboratory Workshop on Colloid Chemistry" Nekrasov AP, Veretenchenko BA, Kharkov NTU "KhPI", 2004
"Characteristic properties of disperse systems" Nekrasov AP, Kharkov, 1996
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