Answer:
0.0015moles
0.135g
Explanation:
Given parameters:
Volume of NaOH = 25mL Â = 0.025L
Molarity of NaOH = 0.12M
Unkown:
Number of moles of oxalic acid = ?
mass of oxalic acid = ?
Solution:
The reaction equation is shown below:
               H₂C₂O₄ + 2NaOH  →  Na₂C₂O₄ + 2H₂O
  Solving:
We should work from the known to the unknown. The known here is NaOH.
##
 Number of moles of NaOH = molarity of NaOH x volume = 0.12 x 0.025 = 0.003mole
##
 From the equation:
    2 moles of NaOH reacted with 1 mole of the acid
   0.03 mole of NaOH will react with [tex]\frac{0.003}{2}[/tex] = 0.0015moles of oxalic acid
##
Mass of oxalic acid = number of moles x molar mass
  Molar mass of oxalic acid = (2 x 1)  + (2 x 12) + (4 x 16) = 90g/mol
Mass of oxalic acid = 0.0015 x 90 = 0.135g of oxalic acid.
Answer:
number of grams of oxalic acid = 0.135 g
Explanation:
Thinking process:
The reaction equation of hydrated oxalic acid  is shown below:
 H₂C₂O₄ + 2NaOH  →  Na₂C₂O₄ + 2H₂O
number of moles of NaOH = concatenation × volume
concentration of NaOH = Â 0.12M
volume of NaOH Â Â Â Â Â Â = 25 ml
                    = 0.025 l
The number of moles   = [tex]0.025 * 0.12\\= 0.003 moles[/tex]
The mole ratio of oxalic acid is half the number of moles of NaOH = [tex]0.5 * 0.003\\= 0.0015 mol[/tex]
Molar mass of oxalic acid  = 90.03
number of moles = [tex]\frac{mass}{molar mass}[/tex]
mass = [tex]number of moles * molar mass\\ = 0.0015 * 90.03\\ = 0.135 g[/tex]
