Acids Bases And Salts

Step 1: The acidified acts as a strong oxidizing agent and reacts with various reducing agents. Step 2: Reactions: (i) With ferrous sulphate: (ii) With : (iii) With oxalic acid: (iv) With sodium thiosulphate:

Step 1: Definition - Molarity (M): Number of moles of solute per liter of solution. - Molality (m): Number of moles of solute per kg of solvent. Step 2: Effect of Temperature - Molarity depends on volume, which changes with temperature due to thermal expansion. Thus, molarity decreases with an increase in temperature. - Molality depends on the mass of the solvent, which remains unaffected by temperature, making it temperature-independent.

Step 1: Calculate moles of HCl.
Molarity (M) Volume (L) = Number of moles

Step 2: Calculate moles of Na CO .

Step 3: Write the neutralization reaction.
From the equation: - 1 mole Na CO requires 2 moles HCl.
- 0.75 mole Na CO would require:

Step 4: Compare available and required HCl.
- Available HCl = 1.0 mol
- Required HCl = 1.5 mol
- Thus, HCl is limiting and all of it will be consumed.

Step 5: Find excess reagent left.
- Na CO left unreacted =
(Since 1.0 mol HCl reacts with 0.50 mol Na CO ).
So, after reaction, unreacted Na CO remains in solution.

Step 6: Nature of the solution.
Unreacted Na CO is basic in nature because it hydrolyzes to give OH ions. Therefore, the resulting solution will be basic.
Correction: On checking again, the leftover species is Na CO , which is alkaline. Thus the correct nature is basic, not acidic.

Step 1: Compare Ethanol and Phenol.
- Ethanol ( ) is a neutral alcohol with very weak acidic character because the bond is not easily ionizable.
- Phenol ( ) is more acidic than ethanol because the phenoxide ion formed after deprotonation is stabilized by resonance in the benzene ring.

Step 2: Compare Phenol and Acetic acid.
- Acetic acid ( ) is much more acidic than phenol because the acetate ion is stabilized by resonance involving two oxygen atoms.

Step 3: Compare Acetic acid and Chloroacetic acid.
- Chloroacetic acid ( ) is stronger than acetic acid because the electron-withdrawing chlorine atom shows the (inductive) effect, which stabilizes the conjugate base (chloroacetate ion).
Final Order:
Thus, the correct option is (C).