Other Chemistry · JEE Main previous year questions

2019 55 questions

1. Q732019 · 12 Apr 2019 · Shift 2

   ${\text{NO}}_2$ required for a reaction is produced by the decomposition of ${\text{N}}_2{\text{O}}_5$ in ${\text{CCl}}_4$ as per the equation, $2{\text{N}}_2{\text{O}}_5\text{(g)}\to 4{\text{NO}}_2\text{(g)}+{\text{O}}_2\text{(g)}$. The initial concentration of ${\text{N}}_2{\text{O}}_5$ is $3.00{\text{ mol L}}^{-1}$ and it is $2.75{\text{ mol L}}^{-1}$ after 30 minutes. The rate of formation of ${\text{NO}}_2$ is :

   1. A.$2.083\times 10^{-3}{\text{ mol L}}^{-1}{\text{ min}}^{-1}$
   2. B.$8.333\times 10^{-3}{\text{ mol L}}^{-1}{\text{ min}}^{-1}$
   3. C.$4.167\times 10^{-3}{\text{ mol L}}^{-1}{\text{ min}}^{-1}$
   4. D.$1.667\times 10^{-2}{\text{ mol L}}^{-1}{\text{ min}}^{-1}$
   Show answer

   Answer: D

2. Q782019 · 12 Apr 2019 · Shift 2

   The compound used in the treatment of lead poisoning is :

   1. A.desferrioxime B
   2. B.Cis-platin
   3. C.D-penicillamine
   4. D.EDTA
   Show answer

   Answer: D

3. Q862019 · 12 Apr 2019 · Shift 2

   The INCORRECT statement is :

   1. A.Lithium is least reactive with water among the alkali metals
   2. B.$\text{LiCl}$ crystallises from aqueous solution as $\text{LiCl}\cdot 2{\text{H}}_2\text{O}$
   3. C.Lithium is the strongest reducing agent among the alkali metals
   4. D.${\text{LiNO}}_3$ decomposes on heating to give ${\text{LiNO}}_2$ and ${\text{O}}_2$
   Show answer

   Answer: D

4. Q872019 · 12 Apr 2019 · Shift 2

   The correct statement is :

   1. A.leaching of bauxite using concentrated NaOH solution gives sodium aluminate and sodium silicate
   2. B.the Hall-Heroult process is used for the production of aluminium and iron
   3. C.pig iron is obtained from cast iron
   4. D.the blistered appearance of copper during the metallurgical process is due to the evolution of ${\text{CO}}_2$
   Show answer

   Answer: A

5. Q902019 · 12 Apr 2019 · Shift 2

   The temporary hardness of a water sample is due to compound X. Boiling this sample converts X to compound Y. X and Y, respectively, are :

   1. A.${\text{Mg(HCO}}_3{)}_2$ and ${\text{MgCO}}_3$
   2. B.${\text{Ca(HO}}_3{)}_2$ and $\text{CaO}$
   3. C.${\text{Ca(HCO}}_3{)}_2$ and ${\text{Ca(OH)}}_2$
   4. D.${\text{Mg(HCO}}_3{)}_2$ and ${\text{Mg(OH)}}_2$
   Show answer

   Answer: D

6. Q622019 · 10 Apr 2019 · Shift 1

   Amylopectin is compound of :

   1. A.$\alpha$-D-glucose, ${\mathrm{C}}_1-{\mathrm{C}}_4$ and ${\mathrm{C}}_1-{\mathrm{C}}_6$ linkages
   2. B.$\beta$-D-glucose, ${\mathrm{C}}_1-{\mathrm{C}}_4$ and ${\mathrm{C}}_2-{\mathrm{C}}_6$ linkages
   3. C.$\beta$-D-glucose, ${\mathrm{C}}_1-{\mathrm{C}}_4$ and ${\mathrm{C}}_1-{\mathrm{C}}_6$ linkages
   4. D.$\alpha$-D-glucose, ${\mathrm{C}}_1-{\mathrm{C}}_4$ and ${\mathrm{C}}_2-{\mathrm{C}}_6$ linkages
   Show answer

   Answer: A

7. Q742019 · 10 Apr 2019 · Shift 1

   At room temperature, a dilute solution of urea is prepared by dissolving 0.60 g of urea in 360 g of water. If the vapour pressure of pure water at this temperature is 35 mm Hg, lowering of vapour pressure will be. (molar mass of urea = $60\mathrm{g}\mathrm{mo}{\mathrm{l}}^{-1}$)

   1. A.0.031 mmHg
   2. B.0.017 mmHg
   3. C.0.028 mmHg
   4. D.0.027 mmHg
   Show answer

   Answer: B

8. Q812019 · 10 Apr 2019 · Shift 1
   
   1. A.3s orbital
   2. B.2s orbital
   3. C.2p orbital
   4. D.1s orbital
   Show answer

   Answer: B

9. Q832019 · 10 Apr 2019 · Shift 1

   The regions of the atmosphere, where clouds form and where we live, respectively, are :

   1. A.Stratosphere and Stratosphere
   2. B.Stratosphere and Troposphere
   3. C.Troposphere and Stratosphere
   4. D.Troposphere and Troposphere
   Show answer

   Answer: D

10. Q852019 · 10 Apr 2019 · Shift 1

    The correct order of catenation is :

    1. A.$\mathrm{C}>\mathrm{Sn}>\mathrm{Si}\approx \mathrm{Ge}$
    2. B.$\mathrm{Si}>\mathrm{Sn}>\mathrm{C}>\mathrm{Ge}$
    3. C.$\mathrm{C}>\mathrm{Si}>\mathrm{Ge}\approx \mathrm{Sn}$
    4. D.$\mathrm{Ge}>\mathrm{Sn}>\mathrm{Si}>\mathrm{C}$
    Show answer

    Answer: C

11. Q862019 · 10 Apr 2019 · Shift 1

    The alloy used in the construction of aircrafts is :

    1. A.Mg – Zn
    2. B.Mg – Al
    3. C.Mg – Mn
    4. D.Mg – Sn
    Show answer

    Answer: B

12. Q682019 · 10 Apr 2019 · Shift 2

    The INCORRECT statement is :

    1. A.the color of $[\mathrm{CoCl}(\mathrm{N}{\mathrm{H}}_3{)}_5{]}^{2+}$ is violet as it absorbs the yellow light.
    2. B.the gemstone, ruby, has $\mathrm{C}{\mathrm{r}}^{3+}$ ions occupying the octahedral sites of beryl.
    3. C.the spin-only magnetic moment of $[\mathrm{Ni}(\mathrm{N}{\mathrm{H}}_3{)}_4({\mathrm{H}}_2\mathrm{O}{)}_2{]}^{2+}$ is 2.83 BM.
    4. D.the spin-only magnetic moments of $[\mathrm{Fe}({\mathrm{H}}_2\mathrm{O}{)}_6{]}^{2+}$ and $[\mathrm{Cr}({\mathrm{H}}_2\mathrm{O}{)}_6{]}^{2+}$ are nearly similar.
    Show answer

    Answer: B

13. Q762019 · 10 Apr 2019 · Shift 2

    The minimum amount of ${\mathrm{O}}_2(\mathrm{g})$ consumed per gram of reactant is for the reaction : (Given atomic mass : Fe = 56, O = 16, Mg = 24, P = 31, C = 12, H = 1)

    1. A.$4Fe(\mathrm{s})+3{\mathrm{O}}_2(\mathrm{g})\to 2F{\mathrm{e}}_2{\mathrm{O}}_3(\mathrm{s})$
    2. B.${\mathrm{P}}_4(\mathrm{s})+5{\mathrm{O}}_2(\mathrm{g})\to {\mathrm{P}}_4{\mathrm{O}}_{10}(\mathrm{s})$
    3. C.${\mathrm{C}}_3{\mathrm{H}}_8(\mathrm{g})+5{\mathrm{O}}_2(\mathrm{g})\to 3C{\mathrm{O}}_2(\mathrm{g})+4{\mathrm{H}}_2\mathrm{O}(\mathrm{l})$
    4. D.$2Mg(\mathrm{s})+{\mathrm{O}}_2(\mathrm{g})\to 2MgO(\mathrm{s})$
    Show answer

    Answer: A

14. Q832019 · 10 Apr 2019 · Shift 2

    The correct statement is :

    1. A.zincite is a carbonate ore.
    2. B.Sodium cyanide cannot be used in the metallurgy of silver.
    3. C.aniline is a froth stabilizer.
    4. D.zone refining process is used for the refining of titanium.
    Show answer

    Answer: C

15. Q842019 · 10 Apr 2019 · Shift 2

    The correct option among the following is :

    1. A.Addition of alum to water makes it unfit for drinking.
    2. B.Colloidal medicines are more effective because they have small surface area.
    3. C.Colloidal particles in lyophobic sols can be precipitated by electrophoresis.
    4. D.Brownian motion in colloidal solution is faster if the viscosity of the solution is very high.
    Show answer

    Answer: C

16. Q852019 · 10 Apr 2019 · Shift 2
    
    1. A.${\mathrm{V}}_{\mathrm{mp}}$ of ${\mathrm{O}}_2(400\mathrm{K})$; ${\mathrm{V}}_{\mathrm{mp}}$ of ${\mathrm{N}}_2(300\mathrm{K})$; ${\mathrm{V}}_{\mathrm{mp}}$ of ${\mathrm{H}}_2(300\mathrm{K})$
    2. B.${\mathrm{V}}_{\mathrm{mp}}$ of ${\mathrm{N}}_2(300\mathrm{K})$; ${\mathrm{V}}_{\mathrm{mp}}$ of ${\mathrm{H}}_2(300\mathrm{K})$; ${\mathrm{V}}_{\mathrm{mp}}$ of ${\mathrm{O}}_2(400\mathrm{K})$
    3. C.${\mathrm{V}}_{\mathrm{mp}}$ of ${\mathrm{H}}_2(300\mathrm{K})$; ${\mathrm{V}}_{\mathrm{mp}}$ of ${\mathrm{N}}_2(300\mathrm{K})$; ${\mathrm{V}}_{\mathrm{mp}}$ of ${\mathrm{O}}_2(400\mathrm{K})$
    4. D.${\mathrm{V}}_{\mathrm{mp}}$ of ${\mathrm{N}}_2(300\mathrm{K})$; ${\mathrm{V}}_{\mathrm{mp}}$ of ${\mathrm{O}}_2(400\mathrm{K})$; ${\mathrm{V}}_{\mathrm{mp}}$ of ${\mathrm{H}}_2(300\mathrm{K})$
    Show answer

    Answer: D

17. Q872019 · 10 Apr 2019 · Shift 2

    A hydrated solid X on heating initially gives a monohydrated compound Y. Y upon heating above 373 K leads to an anhydrous white powder Z. X and Z, respectively, are :

    1. A.Baking soda and dead burnt plaster.
    2. B.Washing soda and soda ash
    3. C.Washing soda and dead burnt plaster.
    4. D.Baking soda and soda ash.
    Show answer

    Answer: B

18. Q682019 · 9 Apr 2019 · Shift 1

    The given plots represent the variation of the concentration of a reactant R with time for two different reactions (i) and (ii). The respective orders of the reactions are : (i) $\ln [R]$ vs time: straight line with negative slope (ii) [R] vs time: straight line with negative slope

    1. A.0,1
    2. B.1,0
    3. C.0,2
    4. D.1,1
    Show answer

    Answer: B

19. Q722019 · 9 Apr 2019 · Shift 1

    Among the following, the set of parameters that represents path function, is : (A) q + w (B) q (C) w (D) H−TS

    1. A.(B) and (C)
    2. B.(A) and (D)
    3. C.(B), (C) and (D)
    4. D.(A), (B) and (C)
    Show answer

    Answer: A

20. Q812019 · 9 Apr 2019 · Shift 1

    For any given series of spectral lines of atomic hydrogen, let $\Delta \bar{v}=\Delta {\bar{v}}_{\max }-\Delta {\bar{v}}_{\min }$ be the difference in maximum and minimum frequencies in $\mathrm{c}{\mathrm{m}}^{-1}$. The ratio $\frac{\Delta {\bar{v}}_{Lyman}}{\Delta {\bar{v}}_{Balmer}}$ is :

    1. A.9 : 4
    2. B.4 : 1
    3. C.27 : 5
    4. D.5 : 4
    Show answer

    Answer: A

21. Q832019 · 9 Apr 2019 · Shift 1

    Excessive release of $\mathrm{C}{\mathrm{O}}_2$ into the atomosphere results in :

    1. A.depletion of ozone
    2. B.polar vortex
    3. C.global warming
    4. D.formation of smog
    Show answer

    Answer: C

22. Q892019 · 9 Apr 2019 · Shift 1

    Magnisium powder burns in air to give :

    1. A.MgO and $\mathrm{M}{\mathrm{g}}_3{\mathrm{N}}_2$
    2. B.MgO only
    3. C.$\mathrm{Mg}(\mathrm{N}{\mathrm{O}}_3{)}_2$ and $\mathrm{M}{\mathrm{g}}_3{\mathrm{N}}_2$
    4. D.MgO and $\mathrm{Mg}(\mathrm{N}{\mathrm{O}}_3{)}_2$
    Show answer

    Answer: A

23. Q832019 · 9 Apr 2019 · Shift 2

    The amorphous form of silica is :

    1. A.kieselguhr
    2. B.quartz
    3. C.tridymite
    4. D.cristobalite
    Show answer

    Answer: A

24. Q882019 · 9 Apr 2019 · Shift 2

    Noradrenaline is a/an

    1. A.Antacid
    2. B.Antihistamine
    3. C.Neurotransmitter
    4. D.Antidepressant
    Show answer

    Answer: C

25. Q892019 · 9 Apr 2019 · Shift 2

    The layer of atmosphere between 10 km to 50 km above the sea level is called as :

    1. A.mesosphere
    2. B.thermosphere
    3. C.troposphere
    4. D.stratosphere
    Show answer

    Answer: D