.Which of the following statements is/are wrong?
(a) van der Waal's radius of iodine is more than its covalent radius
(b) All isoelectronic ions belong to same period of the periodic table
(c) \(I.E._{1}\) of "N" is higher than that of "O" while \(I.E._{2}\) of "O" is higher than that of "N
(d) The electron affinity "N" is almost zero while that of "P" is \(74.3kJmol^{-1}\)

1.Which of the following statements is true: (a) Melting point of Phosphorous is less than that of Nitrogen (b) N_(2) is highly reactive while P_(4) is inert (c)Nitrogen shows higher tendency of catenation than "P" (d) "N-N" is weaker than "P-P"

Which of the following statement are true . (i) In the structure of HNO_3 , the N- O bond (121 pm) is shorter than the N-ON bond (140pm) . (ii) All the P - Cl bonds in PCl_5 are not equivalent . (iii) I - Cl is more reactive than I_2 .

Which of the following atoms and ions are isoelectronic (i.e. Have dor the same number of electrons) with a neon atom a C b. O^(2-) c. n^(Theta) d. F^(o+) e. Na^(o+) f. AI^(3+)

Check the corretness of the following statement about the Bohr model of hydrogen atom: (i) The acceleration of the electron in n = 2 orbit is more than that in n = 1 orbit. (ii) The angular momentum of the electron in n = 2 orbit is more than that in n = 1 orbit. (iii) The KE of the electron in n = 2 orbit is more than that in n = 1 orbit.

Consider the following parameters with regard to hydrogen like atoms: (1). Energy of the atom (2). Radius of electron orbit (3) Spin of the electron Which of the above are same for all hydrogen-like atoms and ions in n=1 state?

Which of the following statements are correct regarding D_(2)O and H_(2)O ? I. D_(2)O reacts with Al_(4)C_(3) at a faster rate than does H_(2)O . II. The freezing point of D_(2)O is higher than that of H_(2)O . III. NaCl is more solution in D_(2)O than in H_(2)O . IV. lonic product of D_(2)O is smaller than that if H_(2)O . Select the correct answer using the codes givem below.

Give reasons for the following: (a) Red phosphorus is less reactive than white phosphorus. (b) Electron gain enthalpies of halogens are largely negative. (c) N_(2)O_(5) is more acidic than N_(2)O_(3) .

Explain the following question (based on ionisation energy): (a) Why IE_(1) of N is higher than that of O atom ? (b) Why IE_(1) of Mg is higher than that of Al atom? (c ) Why IE_(1) of C is greater than that of B atom whereas IE_(2) is reverse ? (d) In general, IE increases along the period (rarr) . Explain why the IE_(2) of Cr is higher than that of Mn (Manganese)? (e) The IE_(1) and IE_(2) of K are 420 and 3050 kJ mol^(-1) respectively and those of Ca are 560 and 1140 kJ mol^(-1) respectively. Compare their values and comment on the differences. (f) The IE of Li , Be and C are 5.5, 9.3 and 11.3 eV . What would be the case and explain. i. K, Ca,Se , ii. N,O,F iii. K^(o+), Ar,Cl^(ɵ) , iv Fe, Fe^(2+), Fe^(3+) v. C,N,O , vi. Cu,Ag,Au vii. K, Rb, Cs , viii Be, B, C ix. Na, Mg, Al (h) Explain why Fe^(2+) is more easily oxidised to Fe^(3+) than Mn^(2+) to Mn^(3+) . (i) Explain whether IE_(1) of two isotopes of same element would be same or different. (j) What are the factors on which IE of main group elements tends to decrease douwn the group (darr) .