Chemical Forums
Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: streakz on October 21, 2004, 02:09:58 AM
-
calculate the normality and equivalent mass of oxalic acid (h2c204) if 20.00ml of oxalic acid solution reacts exactly with 39.0mg of Al(oh)3 (molar mass = 78.0g/mol)
i found that the oxalic equivalent mass is 45.0g
but the normality is 0.075.. dont know how to get that
-
Very simple.Just use the law of equivalents.Remember Equivalents or milliequivalents react in equal number to give equal number 0f equivalents of Products.
Since 39mg of Al[OH]3 reacts completely with the amount present of [COOH]2.
So milliequivalents of [COOH]2=Milliequivalents of AL[OH]3
Equivalent weight of Al[OH]3 is M/3
So 39/78 x 3=20xN [Milliequivalents=NV,where v in ml]
N=0.075N
And you already have calculated the Equivalent weight of [COOH]2.Its M/2