• CBSE/
• AIPMT 2014/
• AIPMT Solved Paper 2011/
• Chemistry

Chemistry 2011

  

Q. 21. Which of the following compounds has the lowest melting point?

(1) CaF₂                                                                (2) CaCl₂

(3) CaBr₂                                                              (4) CaI₂

Sol:

 CaI₂ has lowest melting point

Answer : (4)

 

Q. 22. Which of the following pairs of metals is purified by van Arkel method?

(1) Ni and Fe                                         (2) Ga and In

(3) Zr and Ti                                          (4) Ag and Au

Sol . 

 Zr and Ti are purified by van Arkel method

Answer : (3)

 

Q. 23. The correct order of increasing bond length of C – H, C – O, C – C and C = C is

(1) C -H < C - O < C - C < C = C            

(2) C -H < C = C < C -O < C - C

(3) C -C < C = C < C - O < C -H

(4) C -O < C - H < C - C < C = C

Sol.

Fact

Answer : (2)

 

Q. 24. Acidified K₂Cr₂O₇ solution turns green when Na₂SO₃ is added to it. This is due to the formation of

(1) CrSO₄                                                            (2) Cr₂(SO₄)₃

(3)                                                            (4) Cr₂(SO₃)₃

Sol.

Answer : (2)

 

Q. 25. For the four successive transition elements (Cr, Mn, Fe and Co), the stability of + 2 oxidation state will be there in which of the following order?

(1) Cr > Mn > Co > Fe                            (2) Mn > Fe > Cr > Co

(3) Fe > Mn > Co > Cr                            (4) Co > Mn > Fe > Cr

(At. nos. Cr = 24, Mn = 25, Fe = 26, Co = 27)

Sol.

On the basis of electrode potentials, the correct order is Mn > Fe > Cr > Co

Answer : (2)