Calculating microspheres per gram

During scientific experiment design and analysis it is common to need to know the number of spheres per gram of dry material.? We have put together the table below to help speed up the process.

If you have material of a density different from those listed in the table, divide the number of spheres per gram in the density ~1.0 g/cc column by the true particle density of your material to get an estimate of the number of spheres per gram.

Product Size Polyethylene
Density ~1.0 (g/cc)
Soda Lime Glass
Density ~2.5 (g/cc)
Lower (um) Upper (um) Spheres per Gram Spheres Per Gram
20 27 147,162,715 58,630,564
27 32 74,393,558 29,638,868
32 45 33,467,185 13,333,540
45 53 16,233,536 6,467,544
53 63 9,788,528 3,899,812
63 75 5,813,720 2,316,223
75 90 3,401,258 1,355,083
90 106 2,029,192 808,443
106 125 1,239,525 493,835
125 150 734,672 292,698
150 180 425,157 169,385
180 212 253,649 101,055
212 250 154,941 61,729
250 300 91,834 36,587
300 355 54,371 21,662
355 425 32,196 12,827
425 500 19,305 7,691
500 600 11,479 4,573
600 710 6,796 2,708
710 850 4,025 1,603
850 1000 2,413 961
1180 1400 890 354
1400 1700 513 204
1700 2000 302 120
2000 2360 184 73
2360 2800 111 44
2800 3350 66 26

Note: This table assumes the mean diameter is half way between the upper and lower size.