NEET Questions Solved


The byproduct of Solvay process is:

(a) CO2

(b) NH3

(c) CaCl2

(d) CaCO3

(b) An intermediate reaction in Solvay process gives CaCl2;

      Ca(OH)2 + 2NH4Cl          CaCl2 + 2NH3 + 2H2O

Difficulty Level:

  • 16%
  • 34%
  • 39%
  • 13%

Washing soda is:

(a)Na2CO3

(b) Na2CO3.H2O

(c) Na2CO3.7H2O

(d) Na2CO3.10H2O

(d) Washing soda is chemically Na2CO3.10H2O

Difficulty Level:

  • 13%
  • 4%
  • 9%
  • 76%
NEET - 2016

The suspension of slaked lime in water is known as

(a) limewater

(b) quicklime

(C) milk of lime

(d) aqueous solution of slaked lime

(c) Aqueous solution of slaked lime is called lime water whereas suspension solution of slaked lime is called milk of lime.

Difficulty Level:

  • 19%
  • 23%
  • 52%
  • 7%
NEET - 2016

In context with beryllium, which one of the following statements is incorrect?

(a) It is rendered passive by nitric acid

(b) lt forms Be2C

(c) Its salts rarely hydrolyse

(d) Its hydride is electron-deficient and polymeric

(c) Beryllium salts are covalent in nature because of very small Be2+ ion and its high polarising power, so it is easily hydrolysed, e.g. BeCl2+2H2O Be(OH)2 + 2HCl

Difficulty Level:

  • 17%
  • 27%
  • 38%
  • 20%
NEET - 2015

On heating which of the following releases CO2 most easily?

(a) K2CO3                                 (b) Na2CO3

(c) MgCO3                                 (d) CaCO3

Order of thermal stability is

K2CO3>Na2CO3>CaCO3>MgCO3

Hence, MgCO3 releases CO2 most easily

MgCO3 MgO + CO2

Difficulty Level:

  • 11%
  • 24%
  • 32%
  • 34%
NEET - 2010

Which of the following alkaline earth metal sulphates has hydration enthalpy higher than the lattice enthalpy?

(a) CaSO4               (b) BeSO4

(c) BaSO4               (d) SrSO4

 

(b) Key Idea Hydration energy varies inversely with size and in sulphates of alkaline earth metals lattice energy remains almost constant.

The order of size of alkaline earth metals is

                Be2+<Ca2+<Sr2+<Ba2+

Thus, the order of hydration energy is

                Be2+>Ca2+>Sr2+>Ba2+

Hence, BeSO4 has the hydration enthalpy higher than the lattice enthalpy.

Difficulty Level:

  • 12%
  • 65%
  • 21%
  • 4%

A compound (A) is used in preparation of washing soda to recover ammonia in Solvay's process. When CO2 is bubbled through an aqueous solution of (A), the solution turns milky.It is used in white washing due to disinfectant nature. What is the chemical formula of A?

(a) CaHCO32                       (b) CaO

(c) CaOH2                           (d) CaCO3

(c) NH3Solvay's processNH4ClCaOH2CO2CaCO3A 

Difficulty Level:

  • 13%
  • 18%
  • 46%
  • 25%

CaCl2 is preffered over NaCl for clearing ice on roads particularly in very cold countries. This is because:

(a) CaCl2 is less soluble in H2O than NaCl

(b) CaCl2 is hygroscopic but NaCl is not 

(c) Eutectic mixture of CaCl2/H2O freezes at -55°C while that of NaCl/H2O freezes at -18°C

(d) NaCl makes the road slippery but CaCl2 does not

(c) Due to much lower freezing point of eutectic mixture of CaCl2/H2O.

Difficulty Level:

  • 8%
  • 35%
  • 46%
  • 13%

Which of the following statement is false?

(a) The milk of magnesia used as antacidis chemically MgO + MgCl2

(b) Stability of alkali metal peroxides increases with increase in atomic number

(c) Hydration energy of AgF is higher than its lattice energy

(d) Anhydrous MgCl2 cannot be prepared contains by direct heating of MgCl2 6H2O

(a) Milk of magnesia of MgO + H2O.

Difficulty Level:

  • 36%
  • 19%
  • 26%
  • 20%

A metal [x] on heating on nitrogen gas gives [Y]. [Y] on treatment with H2O gives a colourless gas which when passed through CuSO4 solution gives a blue colour. [Y] is

(A) MgNO32                                     

(B) Mg3N2

(C) NaN3                                             

(D) MgO

(B)

       3Mg+N2             Mg3N2Mg3XN2+6H2O                3YMgOH3+2NH3CuSO4+4NH3                CuNH34SO4  blue colour

Difficulty Level:

  • 16%
  • 57%
  • 17%
  • 12%