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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 ...
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 ...
They may have apparent, effective or equivalent in their names as well. Typically, such units (or indices ) take another latent variable into account, for increased measurement invariance , e.g., apparent temperature , or they are more convenient in a particular context.
Where HV is the hydroxyl value; V B is the amount (ml) potassium hydroxide solution required for the titration of the blank; V acet is the amount (ml) of potassium hydroxide solution required for the titration of the acetylated sample; W acet is the weight of the sample (in grams) used for acetylation; N is the normality of the titrant; 56.1 is ...
The equilibrium is determined by the acid and base dissociation constants (K a and K b) of the involved substances. A special case of the acid-base reaction is the neutralization where an acid and a base, taken at the exact same amounts, form a neutral salt. Acid-base reactions can have different definitions depending on the acid-base concept ...
An example of a reaction forming an ammonium ion is that between dimethylamine, (CH 3) 2 NH, and an acid to give the dimethylammonium cation, [(CH 3) 2 NH 2] +: Quaternary ammonium cations have four organic groups attached to the nitrogen atom, they lack a hydrogen atom bonded to the nitrogen atom.
Its conjugate base is the acetate ion with K b = 10 −14 /K a = 5.7 x 10 −10 (from the relationship K a × K b = 10 −14), which certainly does not correspond to a strong base. The conjugate of a weak acid is often a weak base and vice versa .