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The pH is measured in soil-water (1:1) and soil-salt (1:2 ) solutions. For convenience, the pH is initially measured in water and then measured in CaCl 2 {\displaystyle {\ce {CaCl2}}} . With the addition of an equal volume of 0.02 M CaCl 2 {\displaystyle {\ce {CaCl2}}} to the soil suspension that was prepared for the water pH, the final soil ...
1 kilogram (kg) = 1,000 grams (g) = 2.20462262 lb 1 lb = 453.59237 g = 0.45359237 kg 1 oz = 28.3495231 g. In four different English-language countries of recipe and measuring-utensil markets, approximate cup volumes range from 236.59 to 284.1 milliliters (mL). Adaptation of volumetric recipes can be made with density approximations:
Soil acidification is the buildup of hydrogen cations, which reduces the soil pH. Chemically, this happens when a proton donor gets added to the soil. The donor can be an acid, such as nitric acid, sulfuric acid, or carbonic acid. It can also be a compound such as aluminium sulfate, which reacts in the soil to release protons.
The measurement of pH can become difficult at extremely acidic or alkaline conditions, such as below pH 2.5 (ca. 0.003 mol/dm 3 acid) or above pH 10.5 (above ca. 0.0003 mol/dm 3 alkaline). This is due to the breakdown of the Nernst equation in such conditions when using a glass electrode.
A pH of 9.5 has 10 −9.5 moles hydronium ions per litre of solution (and also 10 −2.5 moles per litre OH −). A pH of 3.5 has one million times more hydronium ions per litre than a solution with pH of 9.5 (9.5 − 3.5 = 6 or 10 6) and is more acidic. [115] The effect of pH on a soil is to remove from the soil or to make available certain ions.
Nutrients in the soil are taken up by the plant through its roots, and in particular its root hairs.To be taken up by a plant, a nutrient element must be located near the root surface; however, the supply of nutrients in contact with the root is rapidly depleted within a distance of ca. 2 mm. [14] There are three basic mechanisms whereby nutrient ions dissolved in the soil solution are brought ...
The solubility of a specific solute in a specific solvent is generally expressed as the concentration of a saturated solution of the two. [1] Any of the several ways of expressing concentration of solutions can be used, such as the mass, volume, or amount in moles of the solute for a specific mass, volume, or mole amount of the solvent or of the solution.
It is very difficult to measure pH values of less than two in aqueous solution with a glass electrode, because the Nernst equation breaks down at such low pH values. To determine pK values of less than about 2 or more than about 11 spectrophotometric [60] [61] or NMR [62] [63] measurements may be used instead of, or combined with, pH measurements.