Search results
Results From The WOW.Com Content Network
Sodium hydrogenoxalate or sodium hydrogen oxalate is a chemical compound with the chemical formula NaHC 2 O 4.It is an ionic compound.It is a sodium salt of oxalic acid H 2 C 2 O 4.It is an acidic salt, because it consists of sodium cations Na + and hydrogen oxalate anions HC 2 O − 4 or HO−C(=O)−CO − 2, in which only one acidic hydrogen atom in oxalic acid is replaced by sodium atom.
A primary standard in metrology is a standard that is sufficiently accurate such that it is not calibrated by or subordinate to other standards. Primary standards are defined via other quantities like length, mass and time. Primary standards are used to calibrate other standards referred to as working standards.
It is the sodium salt of oxalic acid. It contains sodium cations Na + and oxalate anions C 2 O 2− 4. It is a white, crystalline, odorless solid, that decomposes above 290 °C. [2] Sodium oxalate can act as a reducing agent, and it may be used as a primary standard for standardizing potassium permanganate (KMnO 4) solutions.
A typical titration curve of a diprotic acid, oxalic acid, titrated with a strong base, sodium hydroxide.Both equivalence points are visible. Titrations are often recorded on graphs called titration curves, which generally contain the volume of the titrant as the independent variable and the pH of the solution as the dependent variable (because it changes depending on the composition of the ...
The equilibrium constant (K a) for loss of the first proton is 5.37 × 10 −2 (pK a = 1.27). The loss of the second proton, which yields the oxalate ion, has an equilibrium constant of 5.25 × 10 −5 (pK a = 4.28). These values imply, in solutions with neutral pH, no oxalic acid and only trace amounts of hydrogen oxalate exist. [3]
It is necessary to calculate the mass of a solid acid which will react with about 20 cm 3 of this solution (for a titration using a 25 cm 3 burette): suitable solid acids include oxalic acid dihydrate, potassium hydrogen phthalate and potassium hydrogen iodate. The equivalent weights of the three acids 63.04 g, 204.23 g and 389.92 g ...
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 ...
This equation is the equation of a straight line for as a function of pH with a slope of () volt (pH has no units). This equation predicts lower E h {\displaystyle E_{h}} at higher pH values. This is observed for the reduction of O 2 into H 2 O, or OH − , and for reduction of H + into H 2 .