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This sodium hydroxide solution can be used to measure the equivalent weight of an unknown acid. For example, if it takes 13.20±0.03 cm 3 of the sodium hydroxide solution to neutralise 61.3±0.1 mg of an unknown acid, the equivalent weight of the acid is:
An equivalent (symbol: officially equiv; [1] unofficially but often Eq [2]) is the amount of a substance that reacts with (or is equivalent to) an arbitrary amount (typically one mole) of another substance in a given chemical reaction. It is an archaic quantity that was used in chemistry and the biological sciences (see Equivalent weight § In ...
In the technical terms of physical chemistry, the minimum freezing point of a water-salt mixture is −21.12 °C (−6.02 °F) for 23.31 wt% of salt. Freezing near this concentration is however so slow that the eutectic point of −22.4 °C (−8.3 °F) can be reached with about 25 wt% of salt.
Normality can be used for acid-base titrations. For example, sulfuric acid (H 2 SO 4) is a diprotic acid. Since only 0.5 mol of H 2 SO 4 are needed to neutralize 1 mol of OH −, the equivalence factor is: f eq (H 2 SO 4) = 0.5. If the concentration of a sulfuric acid solution is c(H 2 SO 4) = 1 mol/L, then its normality is 2 N. It can also be ...
acid + base (alkali) → salt + water x H y A + y B(OH) x → B y A x + xy H 2 O. For example: HCl + NaOH → NaCl + H 2 O. The statement is still valid as long as it is understood that in an aqueous solution the substances involved are subject to dissociation, which changes the ionization state of the substances. The arrow sign, →, is used ...
It can be prepared by treating a potassium-containing base such as potassium hydroxide or potassium carbonate with acetic acid: CH 3 COOH + KOH → CH 3 COOK + H 2 O. This sort of reaction is known as an acid-base neutralization reaction. At saturation, the sesquihydrate in water solution (CH 3 COOK·1½H 2 O) begins to form semihydrate at 41.3 ...
Salt equivalent is usually quoted on food nutrition information tables on food labels, and is a different way of defining sodium intake, noting that salt is chemically sodium chloride. To convert from sodium to the approximate salt equivalent, multiply sodium content by 2.5:
In domestic cooking, bulk solids, notably flour and sugar, are measured by volume, often cups, though they are sold by weight at retail. Weight measures are used for meat . Butter may be measured by either weight ( 1 ⁄ 4 lb) or volume (3 tbsp) or a combination of weight and volume ( 1 ⁄ 4 lb plus 3 tbsp); it is sold by weight but in ...