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While the VCF is primarily used for liquid hydrocarbons, the theory and principles behind it apply to most liquids, with some exceptions. As a general principle, most liquid substances will contract in volume as temperature drops. However, certain substances, water for example, contain unique angular structures at the molecular level.
Hypocalcemia is a medical condition characterized by low calcium levels in the blood serum. [5] The normal range of blood calcium is typically between 2.1–2.6 mmol/L (8.8–10.7 mg/dL, 4.3–5.2 mEq/L), while levels less than 2.1 mmol/L are defined as hypocalcemic.
In thermodynamics, an activity coefficient is a factor used to account for deviation of a mixture of chemical substances from ideal behaviour. [1] In an ideal mixture, the microscopic interactions between each pair of chemical species are the same (or macroscopically equivalent, the enthalpy change of solution and volume variation in mixing is zero) and, as a result, properties of the mixtures ...
Perhaps the most well known is the dissolution of calcium carbonate to form Ca 2+ and CO 2− 3 (carbonate). The carbonate ion has the potential to absorb two hydrogen ions. Therefore, it causes a net increase in ocean alkalinity. Calcium carbonate dissolution occurs in regions of the ocean which are undersaturated with respect to calcium ...
Gravimetric analysis describes a set of methods used in analytical chemistry for the quantitative determination of an analyte (the ion being analyzed) based on its mass. The principle of this type of analysis is that once an ion's mass has been determined as a unique compound, that known measurement can then be used to determine the same analyte's mass in a mixture, as long as the relative ...
Calcium deposits known as limbus sign may be visible in the eyes. [7] Symptoms are more common at high calcium blood values (12.0 mg/dL or 3 mmol/L). [6] Severe hypercalcaemia (above 15–16 mg/dL or 3.75–4 mmol/L) is considered a medical emergency: at these levels, coma and cardiac arrest can result.
Calcium regulation in the human body. [6]The plasma ionized calcium concentration is regulated within narrow limits (1.3–1.5 mmol/L). This is achieved by both the parafollicular cells of the thyroid gland, and the parathyroid glands constantly sensing (i.e. measuring) the concentration of calcium ions in the blood flowing through them.
The US Institute of Medicine (IOM) established Recommended Dietary Allowances (RDAs) for calcium in 1997 and updated those values in 2011. [6] See table. The European Food Safety Authority (EFSA) uses the term Population Reference Intake (PRIs) instead of RDAs and sets slightly different numbers: ages 4–10 800 mg, ages 11–17 1150 mg, ages 18–24 1000 mg, and >25 years 950 mg. [10]