Answer and Explanation:
The balanced chemical equations are as follows:
The chemical formula of oxalic is 
In the case when oxalic acts reacted with the water so here the oxalic acid eliminates one proton that leads to the development of mono acids
After that, the second step derives that when oxalic acid is in aqueous solution eliminates other proton so it represent the polyprotic acid
Now the chemical equations are as follows:
Elimination of one proton

Now the elimination of other proton

Answer: The net ionic equation will be as follows.

Explanation:
The chemical equation for the given reaction is as follows.

We know that a strong acid or base will dissociate completely into a solvent whereas a weak acid or base dissociates partially into the solvent. Hence, the ionic equation will be as follows.
Now, we will cancel the spectator ions from the above equation. Therefore, the net ionic equation will be as follows.

or,
Answer:
A experimental investigation
Mass of Sulphur dioxide : 256 g
<h3>Further explanation</h3>
Given
Reaction
S + O2 --> SO2 *
Required
Mass of Sulphur dioxide
Solution
mol of Sulphur (Ar=32 g/mol) :
mol = mass : Ar
mol = 128 : 32
mol = 4
From the equation, mol ratio S : SO2 = 1 : 1, so mol SO2 = 4
Mass of SO2 :
mass = mol x MW SO2
mass = 4 x 64
mass = 256 g
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19. the question seems to be answered.
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