I come for days at a task no further! It is:
To 25ml vinegar (CH3COOH) are added a few drops of phenolphthalein. Until the first permanent red coloration of the solution 20ml sodium hydroxide solution of concentration c (NaOH) = 1 mol / l required. Calculate the amount of material, the mass and the mass fraction of dissolved in the vinegar of acetic acid and the molar concentration of acetic acid. Go out in the calculation of the mass fraction of a density p (vinegar) = 1 g / ml.
Until now I could only charge the amount of substance and the mass. If these bills because even right up to now ?:
n = c V n = 1 mol / l n = 0.02l 0,02mol
m = n M M = 60 g / mol m = 0,02mol 60g / mol m = 1.2g
So. Now I need to calculate the mass fraction yes aloud task. But how?? Which formula? And can one explain this also again to me? I have looked to the Internet. But at Wikipedia as I understand simply nothing. Not even the formula.
Thanks in advance!