Oxalic acid is a diprotic acid. If a solid material contains 53.66 percent of oxalic acid (H 2C 2O 4), by mass, then a 0.6543-g sample of that solid will require mL of 0.3483 M NaOH for neutralization. 11.19 97.78 28.59 1.119 22.39

The volume of NaOH required is 22.39 mL

Explanation:

We are given:

Mass of sample = 0.6543 g

Mass percent of oxalic acid = 53.66 %

This means that 53.66 grams of oxalic acid is present in 100 grams of sample

Mass of oxalic acid in the given amount of sample =

Given mass of oxalic acid = 0.351 g

Molar mass of oxalic acid = 90 g/mol

Putting values in above equation, we get:

The chemical equation for the reaction of oxalic acid and NaOH follows:

By Stoichiometry of the reaction:

1 mole of oxalic acid reacts with 2 moles of NaOH

So, 0.0039 moles of oxalic acid will react with = of NaOH

Moles of NaOH = 0.0078 moles

Molarity of solution = 0.3483 M

Putting values in above equation, we get:

Hence, the volume of NaOH required is 22.39 mL

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e