Calculate the concentration of the NaOH solution. If 30,0cm3 of a standard oxalic acid[(COOH)2] solution of concentration 0,5 mol.dm-3,is used to neutralize 25,0 cm3 of a sodium hydroxide (NaOH) solution. The balanced chemical equation for the reation is (COOH)2(aq) + 2NaOH(aq) forms (COONa)2(aq)
How many moles oxalic acid do you have? That is M x L = moles.
Using the coefficients in the balanced equation, convert moles oxalic acid to moles NaOH.
Then M NaOH = moles NaOH/dm^3 NaOH
0,6
To calculate the concentration of the NaOH solution, we can use the concept of stoichiometry.
First, let's determine the number of moles of oxalic acid used in the reaction. We are given that the volume of oxalic acid solution used is 30.0 cm^3 and the concentration is 0.5 mol/dm^3.
To convert the volume from cm^3 to dm^3, we need to divide by 1000:
30.0 cm^3 = 30.0/1000 dm^3 = 0.030 dm^3
To calculate the number of moles of oxalic acid, we multiply the volume (in dm^3) by the concentration:
Number of moles of oxalic acid = volume × concentration
= 0.030 dm^3 × 0.5 mol/dm^3
= 0.015 mol
According to the balanced chemical equation, the stoichiometric ratio between oxalic acid and NaOH is 1:2. This means that for every 1 mole of oxalic acid used, 2 moles of NaOH are consumed.
Since we have determined the number of moles of oxalic acid used in the reaction is 0.015 mol, we can now calculate the number of moles of NaOH present in the reaction.
Number of moles of NaOH = (Number of moles of oxalic acid) × (Stoichiometric ratio of NaOH from balanced equation)
= 0.015 mol × 2
= 0.030 mol
To determine the concentration of the NaOH solution, we need to calculate the number of moles of NaOH per volume (in dm^3) used. The volume of NaOH solution used is given as 25.0 cm^3.
Converting the volume to dm^3:
25.0 cm^3 = 25.0/1000 dm^3 = 0.025 dm^3
Concentration of NaOH solution = (Number of moles of NaOH) / (Volume of NaOH solution used in dm^3)
= 0.030 mol / 0.025 dm^3
= 1.2 mol/dm^3
Therefore, the concentration of the NaOH solution is 1.2 mol/dm^3.