Identify the incorrect statement about halogens. 1) F2 is the best oxidant & non metal with highest S.R.P value 2) the only halogen that oxidises water is Cl2 3)The halogen that occurs in liquid state at 25 degree celsius is Br2 4) Among all halogens I2 having strong Vander waals forces among its molecules.

Which of the statement is/are true about the reactivity of halogenation of alkanes ? The reactivity ordar is F_(2) gt C1_(2) gt Br_(2) gt I_(2) . I. Lower the activation energy for the chain initiation step, more reactive is the halogen. II. Lower the activation energy for the first chain propagation step, more reactive is the halogen. III. More negative is the overall heat of the reaction (Delta H_(r)^(@)) of halogenation ofg alkane, more reactive is the halogen. IV. Lower the activation energy for the second chain-propagation step, more reactives is the halogen.

Pick out the correct statements about the strong nuclear force from the following. S1: It is charge independent. S2: It is the strongest force in nature. S3: Its range is very large. S4: It is responsible for the stability of nuclei.

Statement-1: All halogens are coloured. Statement-2: Halogens exist in diatomic gaseous state. Statement-3: F_(2) is more reactive than Cl_(2)

Which of the following statements about the given reaction are correct? 3Fe(s)+4H_(2)O(g)rarrFe_(3)O_(4)(s)+4H_(2)(g) 1. Iron metal is getting oxidised. 2.Water is getting reduced. 3.Water is acting as reducing agent. 4.Water is acting as oxidising agent.

The IUPAC definition of a transition element is that it is an element that has an incomplete d-subshell in either the neutral atom or its ion. Thus the group 12 elements are member of the d-block but are not transition elements. Chemically solft members of the d-block occurs as sulphide minerals and are partially oxidised to obtain the metal, the more electropositive 'hard' metals occurs as oxides and are extracted by reduction. Opposite to p-block elements, the higher oxidation states are favoured by the heavier elements of d-block Metals on the right of the d-block tend to exist in low oxidation states and form complexes with the ligands. Square-planar complexes are common for the platinum metals and gold in oxidation states that yield d^8 electronic configuration, which include RH(I),Ir(I),Pd(II),Pt(II) and Au(III). The most distinctive features/properties of transition metal complex is their wide range of colours.The crystal field theory attributes the colour of the coordination compounds to d-d transition of the electron.It is important to note that (a) in absence of ligand, crystal field spilling does not occur and hence the substances is colourless, (b) the type of ligand also influences the colour of the complexes. Which of the following has dsp^2 hybridisation and is diamagnetic in nature ? (i) Na_4[Cr(CO)_4] , (ii) [Ni(DMGH)_2] , (iii) [PtHBr(PEt_3)_2] (iv) [As(SCN)_4]^(3-) , (v) [AuBr_4]^(-)

The first (Delta_(i)H_(1)) and second (Delta_(i)H_(2)) ionisation enthalpies ("in" kJ mol^(-1)) and the (Delta_(eg)H^(ө)) electron gain enthalpy ("in" kJ mol^(-1)) of a few elements are given below: {:("Elements",(Delta_(i)H_(1)),(Delta_(i)H_(2)),Delta_(eg)H^(ө)),(I,520,7300,-60),(II,419,3051,-48),(III,1681,3374,-328),(IV,1008,1846,-295),(V,2372,5251,+48),(VI,738,1451,-40):} Which of the above elements is likely to be a. the least reactive element. b. the most reactive metal. c. the most reactive non-metal. d. the least reactive non-metal. e. the metal which can form a stable binary halide of the formula MX_2 (X=halogen). f. the metal which can form a predominantly stable covalent halide of the formula MX(X=halogen).

(a) Complete the following chemical equations for reactions : (i) MnO_(4(aq))^(-) + S_(2)O_(3(aq))^(2-) + H_(2)O_((l)) to (ii) Cr_(2)O_(7 (aq))^(2-) + H_(2)S_((g)) + H_((aq))^(+) to (b) Give an explanation for each of the following observations : (i) The gradual decrease in size (actinoid contraction) from element to element is greater among the actinoids than that among the lanthanoids (lanthanoid contraction.) (ii) The greatest number of oxidation states are exhibited by the members in the middle of a transition series. (iii) With the same d-orbitals configuration (d^(4)) Cr^(2+) ion is a reducing agent but Mn^(3+) ion is an oxidising agent .

Consider the following statements and arrange in the order of true/false as given in the codes . S_1 :Concentrated solution of an alkali metal in liquid ammonia is diamagnetic. S_2 :Increasing stability of the peroxide and super oxide of alkaline earth metal down the group is due to the stabilisation of large anions by large cations through lattice energy effects. S_3 :In the vapour phase BeCl_2 tends to form a chloro-bridged dimer. S_4 :Beryllium hydroxide reacts with acid and alkali both to form [Be(OH_2)_4]Cl_2 and [Be(OH)_4]^(2-) respectively.

If the relative density (R.D.) of a substance is 1.2, state its density in the S.I. system, if density of water at 4^@C is 1000 "kg m"^(-3) .

Consider the following statements and arrange in the order of true/false as given in the codes. S_1 :The hydrogen bond in salt, KHF_2 is stronger than that in gasous HF. S_2 :The dipole moment of CH_3F is greater than that of CH_3Cl . S_3 : sp^2 hybrid orbitals have equals s and p character. S_4 :Two types of bond present in B_2H_6 are covalent and three centre-two electrons bonds.