Other Chemistry · JEE Main previous year questions

2020 54 questions

1. Q542020 · 7 Jan 2020 · Shift 2

   The equation that is incorrect is :

   1. A.$({\Lambda }_m^0{)}_{KCl}-({\Lambda }_m^0{)}_{NaCl}=({\Lambda }_m^0{)}_{KBr}-({\Lambda }_m^0{)}_{NaBr}$
   2. B.$({\Lambda }_m^0{)}_{NaBr}-({\Lambda }_m^0{)}_{NaI}=({\Lambda }_m^0{)}_{KBr}-({\Lambda }_m^0{)}_{NaBr}$
   3. C.$({\Lambda }_m^0{)}_{NaBr}-({\Lambda }_m^0{)}_{NaCl}=({\Lambda }_m^0{)}_{KBr}-({\Lambda }_m^0{)}_{KCl}$
   4. D.$({\Lambda }_m^0{)}_{H_{2}O}=({\Lambda }_m^0{)}_{HCl}+({\Lambda }_m^0{)}_{NaOH}-({\Lambda }_m^0{)}_{NaCl}$
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   Answer: B

2. Q612020 · 7 Jan 2020 · Shift 2

   Which of the following statements is correct ?

   1. A.Gluconic acid can form cyclic (acetal/hemiacetal) structure
   2. B.Gluconic acid is a partial oxidation product of glucose
   3. C.Gluconic acid is obtained by oxidation of glucose with ($\mathrm{HN}{\mathrm{O}}_3$)
   4. D.Gluconic acid is a dicarboxylic acid.
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   Answer: B

3. Q682020 · 7 Jan 2020 · Shift 2
   
   1. A.$A-V_{\text{av}};B-V_{\text{rms}};C-V_{\text{mp}}$
   2. B.$A-V_{\text{rms}};B-V_{\text{mp}};C-V_{\text{av}}$
   3. C.$A-V_{\text{mp}};B-V_{\text{av}};C-V_{\text{rms}}$
   4. D.$A-V_{\text{mp}};B-V_{\text{rms}};C-V_{\text{av}}$
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   Answer: C

4. Q752020 · 7 Jan 2020 · Shift 2· Numerical answer

   The flocculation value of HCl for arsenic sulphide sol. is $30{\text{ m mol L}}^{-1}$ If ${\mathrm{H}}_2\mathrm{S}{\mathrm{O}}_4$ is used for the flocculation of arsenic sulphide, the amount in grams, of ${\mathrm{H}}_2\mathrm{S}{\mathrm{O}}_4$ in 250 ml required for the above purpose is _______. (molecular mass of ${\mathrm{H}}_2\mathrm{S}{\mathrm{O}}_4=98\text{ g/mol}$)

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   Answer: 0.36 to 0.38