What is Porosity?
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To calculate porosity, divide the volume of the empty spaces (pores) by the total volume of the material, often expressed as a percentage: Porosity (P) = (Volume of Pores / Total Volume) x 100%. You can find the pore volume by subtracting the solid volume (determined by density) from the total volume, or by measuring the volume of water that saturates the sample.
Key Formulas & Methods
Using Volume Measurements (Direct Method):
Total Volume (
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): Measure the dimensions of a regular shape, or use water displacement for irregular shapes.
Volume of Pores (
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): Calculate by
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(Volume of Solid).
Example: If a rock's total volume is 100 cmยณ and its solid volume is 70 cmยณ, the pore volume is 30 cmยณ. Porosity = (30/100) * 100...