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Conversion tables
Key information for the working scientist
As a trusted partner with a passion for science, Avantor® offers a broad array of useful conversion tables and formulas to help your research and production to set science in motion.
Particle size1
| Sieve "Mesh" | Sieve Opening | |
|---|---|---|
| Inches | Millimeters | |
| 1 | 1.00 | 25.4 |
| 7/8 | 0.875 | 22.6 |
| 3/4 | 0.750 | 19.0 |
| 5/8 | 0.625 | 16.0 |
| .530 | 0.530 | 13.5 |
| 1/2 | 0.500 | 12.7 |
| 7/16 | 0.438 | 11.2 |
| 3/8 | 0.375 | 9.51 |
| 5/16 | 0.312 | 8.00 |
| .265 | 0.265 | 6.73 |
| 1/4 | 0.250 | 6.35 |
| 3 1/2 | 0.223 | 5.66 |
| 4 | 0.187 | 4.76 |
| 5 | 0.157 | 4.00 |
| 6 | 0.132 | 3.36 |
| 7 | 0.111 | 2.83 |
| 8 | 0.0937 | 2.38 |
| 10 | 0.0787 | 2.00 |
| 12 | 0.0661 | 1.68 |
| 14 | 0.0555 | 1.41 |
| 16 | 0.0469 | 1.19 |
| 18 | 0.0394 | 1.00 |
| 20 | 0.0331 | 0.841 |
| 25 | 0.0278 | 0.707 |
| 30 | 0.0234 | 0.595 |
| 35 | 0.0197 | 0.500 |
| 40 | 0.0165 | 0.420 |
| 45 | 0.0139 | 0.354 |
| 50 | 0.0117 | 0.297 |
| 60 | 0.0098 | 0.250 |
| 70 | 0.0083 | 0.210 |
| 80 | 0.0070 | 0.177 |
| 100 | 0.0059 | 0.149 |
| 120 | 0.0049 | 0.125 |
| 140 | 0.0041 | 0.105 |
| 170 | 0.0035 | 0.088 |
| 200 | 0.0029 | 0.074 |
| 230 | 0.0025 | 0.063 |
| 270 | 0.0021 | 0.053 |
| 325 | 0.0017 | 0.044 |
| 400 | 0.0015 | 0.037 |
1. Large sieve opening (1 to 1/4 inch) have been designated a sieve "mesh" size that corresponds to the size of the opening in inches.
Sieve "mesh" sizes of 31/2 and higher are designated by the number of openings per linear inch in the sieve.
Note: To convert millimeters to microns, move decimal point three places to the right. Example: 0.125 millimeters converts to 125 microns.
Acid / Base Concentrations
Composition of concentrated reagent-grade acids, ammonium hydroxide, and sodium and potassium hydroxide solutions (with dilution directions to 1M and 1N solutions)
| Chemical | Formula Weight of Reagenta | Approximate Density | Approximate Strength of Concd. Reagentb | Assay Limits % w/w | Molarity of Concd. Reagent | Milliliters of Concd. Reagent Necessary to Prepare 1 Liter of 1 Molar Solutionc | Normality of Concd. Reagent | Milliliters of Concd. Reagent Necessary to Prepare 1 Liter of 1 Normal Solutionc |
|---|---|---|---|---|---|---|---|---|
| Acetic Acid (CH3COOH) | 60.052 | 1.05 | 99.8 | 99.7–99.9 | 17.4 | 57.5 | 17.4 | 57.5 |
| Formic Acid (HCOOH) | 46.026 | 1.13 | 90 | 88.0–92.0 | 23.6 | 42.5 | 23.6 | 42.5 |
| Hydrochloric Acid (HCI) | 36.461 | 1.18 | 37.2 | 36.5–38.0 | 12.1 | 82.5 | 12.1 | 82.5 |
| Hydrofluoric Acid (HF) | 20.006 | 1.19 | 49 | 48.0–51.0 | 28.9 | 34.5 | 28.9 | 34.5 |
| Nitric Acid (HNO3) | 63.013 | 1.41 | 69.6 | 69.0–70.0 | 15.6 | 64 | 15.6 | 63 |
| Perchloric Acid (HCIO4) | 100.458 | 1.67 | 70.5 | 70.0–72.0 | 11.7 | 85.5 | 11.7 | 85.5 |
| Perchloric Acid (HCIO4) | 100.458 | 1.67 | 61.3 | 60.0–62.0 | 9.5 | 105.5 | 9.5 | 105.5 |
| Phosphoric Acid (H3PO4) | 97.995 | 1.71 | 85.5 | 85.0–87.0 | 14.8 | 67.5 | 44.4 | 22.5 |
| Sulfuric Acid (H2SO4) | 98.073 | 1.84 | 96 | 95.0–98.0 | 18 | 55.5 | 36 | 28 |
| Ammonium Hydroxide (NH4OH) | 35.046 | 0.90 | 56.6d | — | 14.5 | 69 | 14.5 | 69 |
| Sodium Hydroxide (NaOH) | 39.997 | 1.53 | 50.5 | 50.0–52.0 | 19.4 | 51.5 | 19.4 | 51.5 |
| Potassium Hydroxide (KOH) | 56.105 | 1.45 | 45 | 45.0–46.0 | 11.7 | 85.5 | 11.7 | 85.5 |
a. Based on atomic weight table (32C = 12).
b. Representative value, w/w %.
c. Rounded to nearest 0.5 ml.
d. Equivalent to 28.0 % w/w NH3.