Self Studies

Chemistry Test - 45

Result Self Studies

Chemistry Test - 45
  • Score

    -

    out of -
  • Rank

    -

    out of -
TIME Taken - -
Self Studies

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Self Studies Self Studies
Weekly Quiz Competition
  • Question 1
    1 / -0

    The following acids have been arranged in order of decreasing acid strength. Identify the correct order:

    (I).Cl(OH) 

    (II).Br(OH) 

    (III).I(OH)

    Solution

    In halogens the order of electronegativity of their acid is F>Cl>Br>I.

    Among these acids, Cl is the most electronegative so its acid with OH is more stable with a negative charge.

    (I) HOCl (Strong acid), (II) HOBr, (III) HOI (weak acid)

    So, the correct order of decreasing acid strength is I>II>III

  • Question 2
    1 / -0

    Match List-I with List-II

       List-I (Molecule)    List-II (Bond order)
     A.  Ne2  (i)  1
     B.  N2  (ii)  2
     C.  F2  (iii)  0
     D.  O2  (iv)  3

    Choose the correct answer from the options given below.

    Solution

    (A) Ne2(20e)

    σ1 s2σ1 s2σ2 s2σ2 s2σ2pz2π2px2π2py2π2px2π2py2σ2pz2

    Bond order =10102=0 (iii) of List-II.

    (B) N2(14e)

    σ1 s2σ1 s2σ2 s2σ2 s2π2px2,π2py2σ2p Bond order =1042=3 (iv) of List-II.

    (c) F2(18e)

    σ1 s2σ1 s2σ2 s2σ2 s2σ2pz2π2px2π2py2π2py2π2

    Bond order =1082=1( i) of List-II.

    (d) O2(16e)

    σ1 s2σ1 s2σ2 s2σ2 s2σ2pz2π2px2π2py2π2px1π2py1

    Bond order =1062=2 (ii) of List-II.

    The correct matching is option (a).

    No. of electrons in antibonding

    MO (Molecular Orbital)

    Note : Bond order = No. of electrons in bonding MO 2

  • Question 3
    1 / -0

    A catalyst is added to a reaction to increase the rate of reaction. Which of the following statements is correct?

    Solution

    A catalyst works by providing an alternative reaction pathway to the reaction product. The rate of the reaction is increased as this alternative route has lower activation energy than the reaction route not mediated by the catalyst.

  • Question 4
    1 / -0

    Generally transition elements form coloured salts due to the presence of unpaired electrons. Which of the following compounds will be coloured in solid state?

    Solution

    In Ag2SO4, silver is present as Ag+, in CuF2, copper is present as Cu2+, in ZnF2, zinc is present as Zn2+, in Cu2Cl2, the copper is present as Cu+1.

    As they are metal cations, the electrons are removed from their actual configuration to form ions.

    The respective transition elements exists in:

    Ag+[Ar]4d105s0, (have completely filled d orbital).

    Cu+2[Ar]3d94s0, (have incompletely filled d orbital).

    Zn+2[Ar]3d104s0, (have completely filled d orbital).

    Cu+1[Ar]3d104s9, (have completely filled d orbital).

    Since, Cu+2 has unpaired electron, it will show electron transitions. Therefore, will be coloured.

  • Question 5
    1 / -0

    A well-stoppered thermos flask contains some ice cubes. This is an example of:

    Solution

    A well-stoppered thermos flask contains some ice cubes. This is an example of an isolated system.

    An isolated system is a thermodynamic system that can not exchange either energy or matter outside the boundaries of the system.In a thermos, ice can be kept for many hours because the walls of the thermos are insulated and it does not allow heat to flow out of the flask.

  • Question 6
    1 / -0

    The functional group present in organic, acid is –

    Solution

    The functional group present in organic, acid is –COOH.

    The organic acids are known as carboxylic acid as the functional group is carboxyl group. This is the structure of the organic acid where R can be an alkyl or benzyl group and –COOH is the functional group. They are known as carboxylic acids. Their general formula is CnH2nO2.

  • Question 7
    1 / -0

    Transition metal compounds are usually coloured. This is due to the electronic transition:

    Solution

    Transition metal compounds are usually coloured. This is due to the electronic transition within the d-orbitals.

    Transition elements (also known as transition metals) are elements that have partially filed d orbitals.

    Many ionic and covalent compounds of transition elements are coloured and this colouring property is due to dd electronic excitation. The colour of the compound is complementary to the colour absorbed.

  • Question 8
    1 / -0

    Which statement is correct?

    Solution

    Maleic acid is stronger than fumaric acid.

    • Maleic acid is cis-butenedioic acid whereas fumaric acid is trans-butenedioic acid.
    • Maleic acid is able to lose H+ion and it results in the formation of intra hydrogen bond. Whereas fumaric acid being a trans isomer has strong interaction with both the oxygen atoms of each carboxylic group. Therefore, fumaric acid is unable to give hydrogen ions as compared to maleic acid.
    • That is why, maleic acid is stronger than fumaric acid.
  • Question 9
    1 / -0

    NH3 and BF3 Form an adduct readily because they from:

    Solution

    BF3-

    • This moleculedoes nothave its octetfulfilled.
    • To fill its octet, it canaccepta lone pair and act as aLewis acid.

    NH3-

    • Nitrogen has anextra lone pairon its head.
    • To get rid of it it candonatethis pair acting as aLewis base.

    The interaction-

    • Lewis acid has avacant unoccupied orbital called LUMO.
    • Lewis bases have fulfilled occupiedorbital called HOMO.
    • Electron density from HOMO is donated toLUMOof Lewis acid.
    • A simple HOMO and LUMOi nteraction is shown below:

    • Thisdonationof electron density forms acovalent coordinate betweenNH3and BF3.

    Aco-ordinate bond exists between NHand BF3.

  • Question 10
    1 / -0

    The disperse phase in colloidal iron (III) hydroxide and colloidal gold is positively and negatively charged, respectively. Which of the following statements is NOT correct?

    Solution

    We know a negatively charged gold solution is coagulated by a Magnesium Chloride solution readily than positively charged iron (III) hydroxide solution. Also, in Magnesium chloride, the charge on cation is twice the charge on the anion. Higher is the charge on ion, higher will be its coagulating power.

    Also we have studied that Sodium sulphate solution causes coagulation in both solutions. Negatively charged gold sol is coagulated by sodium ions and positively charged iron (III) hydroxide sol is coagulated by sulphate ions.

    The dispersed phase in colloidal gold and colloidal iron (III) hydroxide is negatively and positively charged respectively. Mutual Coagulation is affected when two solutions are mixed.. This is due to neutralization of the charge on one sol by opposite charge on another sol.

    By electrophoresis, coagulation in both the solutions can be brought. We know that, during electrophoresis, through the colloidal solution an electric current is passed and the experiment is arranged in such a manner that only particles can move.

    After studying above points, we can conclude that option A, B and D are correct and C is incorrect.

Self Studies
User
Question Analysis
  • Correct -

  • Wrong -

  • Skipped -

My Perfomance
  • Score

    -

    out of -
  • Rank

    -

    out of -
Re-Attempt Weekly Quiz Competition
Self Studies Get latest Exam Updates
& Study Material Alerts!
No, Thanks
Self Studies
Click on Allow to receive notifications
Allow Notification
Self Studies
Self Studies Self Studies
To enable notifications follow this 2 steps:
  • First Click on Secure Icon Self Studies
  • Second click on the toggle icon
Allow Notification
Get latest Exam Updates & FREE Study Material Alerts!
Self Studies ×
Open Now