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Engineering
130 Views   |  

The dions, in octahedral field of weak field ligands will have the configuration

  • Option 1)

  • Option 2)

  • Option 3)

  • Option 4)

 
As we learnt in  Weak field Ligand - These are the ligands which do not pair the electron in inner d-orbital. - wherein For example:  etc        Weak field Ligands do not pair electrons in  t2g orbitals so, the configuration will be    Option 1) This option is incorrect Option 2) This option is incorrect Option 3) This option is correct Option 4) This option is incorrect
Engineering
129 Views   |  

The color of Mohr's salt \left ( NH_{4} \right )_{2} SO_{4}\:Fe\left ( SO_{4}\right ).6H_{2}O  is :

  • Option 1)

    White

  • Option 2)

    Green

  • Option 3)

    Violet

  • Option 4)

    Blue

 
As we learnt in  Pseudoalums - Double sulphates of divalent ions and trivalent ions, which are not isomorphous with alums - wherein    Mohr's salt or Ammonium iron (II) sulphate is green in colour.    Option 1) This option is incorrect Option 2) This option is correct Option 3) This option is incorrect Option 4) This option is incorrect
Engineering
665 Views   |  

The CFSE for octahedral [ CoCl6]4- is 18,000 cm -1. The CFSE for tetrahedral [CoCl4]2- will be

  • Option 1)

    18,000 cm -1

  • Option 2)

    16,000 cm -1

  • Option 3)

    8,000 cm -1

  • Option 4)

    20, 000 cm-1

 
As we learnt in  Comparison in delta o and delta t - -       Option 1) 18,000 cm -1 This option is incorrect  Option 2) 16,000 cm -1 This option is incorrect  Option 3) 8,000 cm -1 This option is correct  Option 4) 20, 000 cm-1 This option is incorrect 
Engineering
196 Views   |  

The central atoms or ions in a coordination entity behaves as:

  • Option 1)

    Lewis Base

  • Option 2)

    Lewis Acid

  • Option 3)

    Arrhenius Acid

  • Option 4)

    Bronsted Acid

 
As we learnt in  Coordination Entity - Comparises of a central metal atom or ion bonded to a  fixed no of ions or molecules - wherein eg:                                            Coordination                      entity   According to the Lewis theory of acids and bases, an entity that accepts a pair of electrons acts as an acid. The central atoms form coordinate bonds and accept pair of...
Engineering
91 Views   |  

The C.F.S.E. for the complex K_{4}[Fe(CN)_{6}] is:

  • Option 1)

    0.6 \Delta_{o}

  • Option 2)

    -3.6 \Delta_{o}

  • Option 3)

    -2.4 \Delta_{o}

  • Option 4)

    -0.4 \Delta_{o}

 
As we learnt in  CFSE in octahedral complex - -   Electronic Configuration of  in  ,  as CN- is a strong ligand. Therefore, CFSE in Octahedral Complexes.    Option 1) This answer is incorrect Option 2) This answer is incorrect Option 3) This answer is correct Option 4) This answer is incorrect
Engineering
121 Views   |  

The borex based test can be used tto detect the presence of

  • Option 1)

    Al^{3+}

  • Option 2)

    Mg^{2+}

  • Option 3)

    Ni^{2+}

  • Option 4)

    Na^{+}

 
As we learnt in Borax Bead Test - B2O3 on heating combines with a number of coloured transition metal oxides Co, Ni, Cr, Cu, Mn, etc. to form correspending metaborates which posses characteristic colour. - wherein Cobalt metaborate (blue)   B2O3 on heating, reacts with a number of transition metal oxides, Co, Ni, etc. to form metaborates that have a characteristic colour.          Option...
Engineering
166 Views   |  

Structural units of ice and dry ice are respectively

  • Option 1)

    H_{2}O,CO

  • Option 2)

    H_{2}O,H_{2}O

  • Option 3)

    CO_{2},H_{2}O

  • Option 4)

    H_{2}O,CO_{2}

 
As we learnt in  Dry ice - Used as a refrigerant for ice-cream and frozen food -   Ice = H2O Dry ice = Solid CO2     Option 1) This answer is incorrect Option 2) This answer is incorrect Option 3) This answer is incorrect Option 4) This answer is correct
Engineering
207 Views   |  

Optical isomerism is not shown by the complex :

 

(Ox = Oxalate & en = ethylenediamine)

  • Option 1)

    \left [ Cr (ox)_{3} \right ]^{3-}

  • Option 2)

    \left [ Co(en)_{2} \right Cl_{2} ]^{+} (Cis-form)

  • Option 3)

    \left [ Co(en)_{2} \right Cl_{2}]^{+} (trans-form)

  • Option 4)

    \left [ Cr(en)_{3} \right ]^{3+}

     

 
As we learnt in  Optical Isomerism - Optical isomers are mirror images that cannot be suprimposed on one another -    Trans  Clearly, we can superimpose its mirror image on itself. So it won't show optical isomerism.   Option 1) This answer is incorrect Option 2) This answer is incorrect Option 3) This answer is correct Option 4)   This answer is incorrect
Engineering
153 Views   |  

Dipole moment and ionisation constant are maximum in case of 

  • Option 1)

    HF, HF

  • Option 2)

    HF, HIHF, HI

  • Option 3)

    HI, HF

  • Option 4)

    HI,HI

 
As we learnt in  Acidic strength of Hydride - HI>HBr>HCl>HF - wherein Increases down the group    Dipole moment of Hydride - HF>HCl>HBr>HI - wherein Deacreses due to decrease in electronegativity difference    Dipole moment is maximum when electronegative difference is maximum i.e. in case of HF. Ionization constant of HI>HF as it's value increases down the group due to weakening of...
Engineering
96 Views   |  

Coordination number and oxidation number of Cr in 

K_{3}\left [Cr \left (C_{2}O_{4}\right )_{3} \right ] are respectively:

  • Option 1)

    4 and +2

  • Option 2)

    6 and +3

  • Option 3)

    3 and +3

  • Option 4)

    3 and 0

 
As we learnt in  Chelate ligands and Chelate complex - When a di or polydentate ligand uses its two or more donor atom to bind a single metal atom to form a cycle ring, it is known as chelate ligand. Complex formed by chelate ligands are called chelate compound.  - wherein Chelate complex are more stable than ligands containing unidentate ligand.    is a chelate ligand and forms two coordinate...
Engineering
121 Views   |  

Calomel is:

  • Option 1)

    Hg_{2}Cl_{2}\: and\: Hg

  • Option 2)

    HgCl_{2}

  • Option 3)

    Hg+HgCl_{2}

  • Option 4)

    Hg_{2}Cl_{2}

 
As we learnt in  Reaction with Mercury (I) Chloride with Chlorine - - wherein Cl2 oxidise Hg22+  into Hg2+   Calomel is Mercury (I) chloride with the formula Hg2Cl2. It was earlier used in medicine as a laxative.    Option 1) This answer is incorrect Option 2) This answer is incorrect Option 3) This answer is incorrect Option 4) This answer is correct
Engineering
92 Views   |  

Borazine is 

  • Option 1)

    Isoelectronic with nepthalene

  • Option 2)

    Isosteric with Anthracene

  • Option 3)

    Both Isosteric and Isoelectronic with Benzene

  • Option 4)

    None of these

 
As we learnt in  Reaction of diborane with ammonia - Gives borazine (B3N3H6), known as inorganic benzene - wherein   Borazine (also called inorganic benzene) is B3N3H6  Clearly it has same number of atoms and same number of electrons. It is both isosteric and isoelectronic with benzene.    Option 1) Isoelectronic with nepthalene This answer is incorrect Option 2) Isosteric with...
Engineering
85 Views   |  

Amongst Ni(CO)_{4},  [Ni(CN)_{4}]^{-2}     and  [NiCl_{4}]^{-2}

  • Option 1)

    Ni(CO)_{4}, and [NiCl_{4}]^{-2} are diamagnetic and [Ni(CN)_{4}]^{-2} is paramagnetic.

  • Option 2)

    [NiCl_{4}]^{-2}  and  [Ni(CN)_{4}]^{-2}  are diamagnetic and Ni(CO)_{4}, is paramagnetic.

  • Option 3)

    Ni(CO)_{4},  and  [Ni(CN)_{4}]^{-2}  are diamagnetic and  [NiCl_{4}]^{-2} is paramagnetic.

     

     

  • Option 4)

    Ni(CO)_{4}, is diamagnetic and [NiCl_{4}]^{-2}  and  [Ni(CN)_{4}]^{-2}  are paramagnetic.

 
As we learnt in  Diamagnetism - When substance unaffected by a magnetic field or the central metal atom doesn't have unpaired e- called Diamagnetic substance or character. - wherein No unpaired e-   Paramagnetism - When a substance is attracted by a magnetic field or have unpaired  e-  called paramagnetic substance. - wherein 5 unpaired e-     Lets take each species individually Ni (CO)4 : Ni...
Engineering
372 Views   |  

A transition metal X has a configuration [Ar] 3d4 in its +3 oxidation state. What is its atomic number?:

  • Option 1)

    25

  • Option 2)

    26

  • Option 3)

    22

  • Option 4)

    23

 
As we learnt in  'd' Block in periodic table - In periodic table, the 'd' block elements are present between s and p block elements by the position and the three rows of transition metal are  3d 4d 5d, the 6d series is still incomplete. - wherein   Atmoic number of Ar is 18. Add 4 for the the d-electrons. Then add 3 more for the Oxidation state.  Hence, Atomic no. = 18+4+3 = 25     Option...
Engineering
124 Views   |  

XeF_{6}  cannot be stored in glass because

  • Option 1)

    it doesn't react

  • Option 2)

    It reacts with SiO_{2}

  • Option 3)

    It reacts with HCl

  • Option 4)

    Both a and c

 
As we learnt in  Structure of Xenon hexafluoride - Distorted octahedral and hybridisation is Sp3d3 - wherein   XeF6 cannot be stored in glass because it reacts with the silica present and gives the explosive XeO3   Option 1) it doesn't react This answer is incorrect Option 2) It reacts with This answer is correct Option 3) It reacts with HCl This answer is incorrect Option 4) Both a and...
Engineering
163 Views   |  

p\pi-p\pi multiple bonds occur between

  • Option 1)

    C and C

  • Option 2)

    C and O

  • Option 3)

    C and N

  • Option 4)

    All of these

 
As we learnt in Structure of Carbon dioxide - Non planar linear molecule - wherein Due to maximum tendency to form multiple bond with oxygen    -   bonds are formed by overlapping of p-orbitals that are perpendicluar to the nuclear axis.  CO, CN, CC all show  -   bonding.  Option 1) C and C This answer is incorrect Option 2) C and O This answer is incorrect Option 3) C and N This answer is...
Engineering
160 Views   |  

Cu_{2}O is 

  • Option 1)

    Black Oxide of Copper

  • Option 2)

    Copper Oxide

  • Option 3)

    Red Oxide of Copper

  • Option 4)

    Cupric Oxide

 
As we learnt in  Oxides of 3d metals - The ability of oxygen to stabilise the highest oxidation number in the oxides of 'd' block elements are shown in the table or shown in fig.   -    Cu2O is red coloured oxide of copper. Whereas CuO is black coloured oxide.    Option 1) Black Oxide of Copper This answer is incorrect Option 2) Copper Oxide This answer is incorrect Option 3) Red Oxide of...
Engineering
97 Views   |  

BF_{3}  reacts with water to give HBF_{4} what is the change in hybridization

  • Option 1)

    Sp^{2}\, \, to \, \, Sp^{3}

  • Option 2)

    Sp^{3}\, \, to \, \, Sp^{2}

  • Option 3)

    Sp\, \, to \, \, Sp^{3}

  • Option 4)

    Sp^{2}\, \, to \, \, Sp^{3}d

 
As we learnt in Concept Reaction of Boron Trifluoride with water - Does not undergo hydrolysis due to strong B-F bond, but reacts with water to form an adduct - wherein   BF3 reacts with water to form an adduct  The Hybridisation of B goes from sp2 in BF3  to sp3  in  Option 1) This answer is correct Option 2) This answer is incorrect Option 3) This answer is incorrect Option 4) This...
Engineering
101 Views   |  

Al_2O_3\, \, and \, \, Al(OH)_3 \, \, both\, \, are

  • Option 1)

    Acidic

  • Option 2)

    basic

  • Option 3)

    Amphoteric

  • Option 4)

    All of these

 
As we learnt in  Hydroxides of boron family - General formula: Acidity decreases, basicity increases down the group - wherein Aluminium hydroxide is amphoteric   Oxides of boron family - Acidity decreases and basicity increases down the group General formula: M2O3 - wherein Aluminium oxide is amphoteric   In the oxide and hydroxides of the Boron family, the acidity decreases and basicity...
Engineering
123 Views   |  

 the highest magnetic moment for transition metal exists for

  • Option 1)

    3d^{9}

  • Option 2)

    3d^{7}

  • Option 3)

    3d^{5}

  • Option 4)

    3d^{3}

 
As we learnt in  Calculation of spin only magnetic moment - where n = no. of unpaired electron  - wherein     n = Number of unpaired electrons Therefore, maximum unpaired electrons give highest magnetic moment. 3d5 has 5 unpaired electrons, higher than any other species.                  Option 1) This answer option is incorrect Option 2) This answer option is incorrect Option...
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