A chemistry student weighs out of citric acid , a triprotic acid, into a volumetric flask and dilutes to the mark with distilled water. He plans to titrate the acid with solution. Calculate the volume of solution the student will need to add to reach the final equivalence point. Be sure your answer has the correct number of significant digits.

47.7 mL

Explanation:

There is some info missing. I think this is the original question.

A chemistry student weighs out 0.306 g of citric acid (H₃C₆H₅O₇), a triprotic acid, into a 250. mL volumetric flask and dilutes to the mark with distilled water. He plans to titrate the acid with 0.1000 M NaOH solution. Calculate the volume of NaOH solution the student will need to add to reach the equivalence point. Be sure your answer has the correct number of significant digits.

First, let's calculate the moles of citric acid (MW 192.12 g/mol).

0.306 g × (1 mol/192.12 g) = 1.59 × 10⁻³ mol

Let's consider the neutralization reaction between H₃C₆H₅O₇ and NaOH.

H₃C₆H₅O₇ + 3 NaOH → Na₃C₆H₅O₇ + 3 H₂O

The molar ratio of H₃C₆H₅O₇ to NaOH is 1:3. The moles of NaOH are 3 × 1.59 × 10⁻³ mol = 4.77 × 10⁻³ mol

The volume of 0.1000 M NaOH solution that contains 4.77 × 10⁻³ moles is:

4.77 × 10⁻³ mol × (1000 mL/0.1000 mol) = 47.7 mL

the answer is learned

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-