Question

What are the dimensions of an extra small square of a hemocytometer:

oint Cover glass Counting chambers 0.1 mm sample depth Cover glass montimg suppon Extra Small square Small square Counting grid (centrel area) Large Square Imm

My guess is 1/20 mm by 1/16mm. Converted to micrometers this would be 50 micrometers by 62.5 micrometers. I just want to make sure I haven't made any errors.

Answer 1

The dimension of extra small square is 0.05 mm.

This is because the central large square contains 25 small square. Area of each small square is 0.04mm². Each small square contains 16 extra small square. So dividing 0.04/16 = 0.0025 mm².This is the area of one extra small square so to find out the dimension of a square whose area is 0.0025 mm² we will simply square root it to get a dimension of 0.05mm

To cross check let us multiply dimension of of one extra small square- 0.05 X 0.05 = 0.0025mm²

Now there are 16 extra small square in a small square so total area of small square will be- 0.0025mm² X 16 = 0.04mm²

Now there are 25 small squares so total area of 25 small squares is- 0.04mm² X 25 = 1mm²

Thus 1mm² is the area of one large square.

Hope you like the answer.