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Chemistry Entrance Test - 1

A test by Muggu.

Test Questions

Question

The radius of the Polonium 210 nucleus may be taken as 8.3 fm. What is the radius of the iron –56 nucleus ? $[1fm=10^{-15}]$

Answers

Correct	Answer Text
	6.22
	6.56
	5.35
	0.714

Question

How does the electrical conductivity of 20 ml of 0.2 M MgSO_4 change when 0.5 M Ba(OH)_2 solution is gradually added to it to excess?

Answers

Correct	Answer Text
	decreases
	increases then decrease
	increases
	decreases then increases

Question

In a reversible reaction $A\overset {k_1}{\underset {k_2}{\leftrightharpoons}}B$ the initial concentration of A and B are a and b in moles per litre and the equilibrium concentration are (a-x) and (b+x) respectively: express x in terms of k_1, k_2 a and b.

Answers

Correct	Answer Text
	$\frac {k_1a-k_2b}{k_1k_2}$
	$\frac {k_1a-k_2b}{k_1-k_2}$
	$\frac {k_1a+k_2b}{k_1+k_2}$
	$\frac {k_1a-k_2b}{k_1+k_2}$

Question

An octahedral complex $[Co \quad A_4B_2]^+$ reacts with B^-
$[Co \quad A_4B_2]^++B^-\rightarrow [CoA_3B_3]+A$
Assuming that the initial complex ion is a mixture of isomeric forms how many isomeric products are possible?

Answers

Correct	Answer Text
	only one
	four
	three
	two

Question

Of the four compounds given below, which may be expected to have the highest melting point?

Answers

Correct	Answer Text

Question

The formula of a the copper salt of a monobasic acid is CuA_2.nH_2O (HA is the formula of the acid ). 1 gram of the salt on strong heating leaves behind 0.331 gram of CuO. Given that the equivalent weight of the acid is 62.58. What is the value of n?

Answers

Correct	Answer Text
	3
	4
	1
	2

Question

Which of the following reactions is not possible ?

Answers

Correct	Answer Text
	$C_6H_5-NH_2+3KOH+CHCl_3\rightarrow C_6H_6.NC+3KCl+3H_2O$
	$C_6H_5-NH_2+CH_3CHO\rightarrow C_6H_5-N=CH.CH_3$

Question

Which of the following ligands would not have chelating effect with metal ions?

Answers

Correct	Answer Text


	$C_2O_4^{2-}$

Question

A certain solid mixed oxide crystallizing in the cubic system contains cations M_1 and M_2 and the oxide ion $O_{2-}$ . Each M_1 ion is surrounded by 12 equidistant nearest neighbor oxide ions. If the oxide ions occupy face centers of the cubic unit cell, where are the M_1 ions situated?

Answers

Correct	Answer Text
	Occupying half the number of edge centers
	At the centre of unit cell
	At the corners of the cube
	At the edge centers

Question

A certain oxide of iron contains 2.5 grams of oxygen for every 7.0 grams of iron. If it is regarded as a mixture of FeO and Fe_2O_3 , in the weight ratio x:y, what is x:y, (atomic weight of iron = 56)

Answers