One gram of a mixture of Na2CO3 and NaHCO3consumesy equivalents of HCl for complete neutalisation One gram of the mixture - Chemistry - Redox reactions

Question

One gram of a mixture of
Na2CO3 and
NaHCO 3
consumesy equivalents of HCl for complete
neutalisation One gram of the mixture is strongly heated,
then cooled and the residue is treated with HCl How many
equivalents of HCl would be required for complete
neutralisation?
A 2y
B y
C 3y/4
D 3y/2

Vartika Jain · Accepted Answer

Dear Student,

Let the amount of Na2CO3 in the mixture be x gSo, the amount of NaHCO3= (1-x) gMoles of Na2CO3=MassMolar mass=x106 mol and, moles of NaHCO3=1-x84molNa2CO3 + 2HCl → 2NaCl + H2O +CO2  1 mol         2 molNaHCO3 + HCl → NaCl + H2O +CO21 mol           1 mol1 mol of Na2CO3 reacts with 2 mol of HClSo, x106of Na2CO3 reacts with 2x106 mol of HClSimilarly, 1 mol of NaHCO3 reacts with 1 mol of HClSo, 1-x84 mol of NaHCO3 reacts with 1-x84 mol of HClTotal moles of HCl=2x106+1-x84 and  Moles of HCl= equivalents of HCl    ( since n-factor for HCl =1)or, 2x106+1-x84= yor, 168x+106-106x8904= yor, 62x+1068904=y   
(i)On heating the mixture of NaHCO3 and Na2CO3 only NaHCO3 decomposed according to the following equation2NaHCO3 →∆ Na2CO3 + H2O +CO22 mol of NaHCO3 decomposes to 1 mol of Na2CO3So, 1-x84mol of NaHCO3 decomposes to 12×1-x84mol =1-x168molSo, Moles of Na2CO3 =1-x168+x106=106-106x+168x17808=106+62x17808=53+31x8904Moles of NaHCO3 = 0Now, 1 mol of Na2CO3 reacts with 2 mol of HClSo, 53-31x8904 mol of Na2CO3 will react with 2×53+31x8904=106+62x8904 mol of HClTotal moles of HCl used = 106+62x8904 = y   (from (i))So, equivalents of HCl required = yHence, the correct answer is B

One gram of a mixture of Na2CO3 and NaHCO 3 consumesy equivalents of HCl for complete neutalisation.One gram of the mixture is strongly heated, then cooled and the residue is treated with HCl. How many equivalents of HCl would be required for complete neutralisation? A. 2y B. y C. 3y/4 D. 3y/2

One gram of a mixture of Na₂CO₃ and NaHCO ₃consumesy equivalents of HCl for complete neutalisation.One gram of the mixture is strongly heated, then cooled and the residue is treated with HCl. How many equivalents of HCl would be required for complete neutralisation?
A. 2y
B. y
C. 3y/4
D. 3y/2