The correct order of electronegativity is
1.Cl > F > O > Br
2. F > O > Cl > Br
3. F > Cl > Br > O
4. O > F > Cl > Br
Find the successive elements of the periodic table with ionisation energies, 2372, 520 and 890 kJ per mol respectively
1. Li, Be, B
2.H, He, Li
3.B, C, N
4.He, Li, Be
For the same value of n, the penetration power of orbital follows the order
1.s = p = d = f
2. p > s > d > f
3. f < d < p < s
4.s < p < d < f
In the modern periodic table, the number of period of the element is the same as
1. principal quantum number
2.atomic number
3.azimuthal quantum number
4.atomic mass
The correct order for the size of I, I+, I– is
1. I > I– > I+
2. I > I+ > I–
3. I– > I > I+
4. I+ > I– > I
Two different beakers contain M1-O-H, and M2-O-H solutions separately. Find the nature of the two solutions if the electronegativity of M1Â = 3.4, M2Â = 1.2, O = 3.5, H = 2.1
1. acidic, acidic
2.basic, acidic
3. basic, basic
4.acidic, basic
Which of the following statements is incorrect?
1.I.E.1Â of O is lower than that of N but I.E.2Â O is higher than that of N
2.The enthalpy of N to gain an electron is almost zero but of P is 74.3 kJ mol-1
3.isoelectronic ions belong to the same period
4.The covalent radius of iodine is less than its Van der Waal’s radius
Which of the reactions will need the maximum amount of energy?
1.Na → Na+ + e–
2. Ca+ → Ca++ + e–
3.K+ → K+ ++ e–
4.C2+ → C3+ + e–
Which one is the most acidic among these?
1. MgO
2.CaO
3.Al2O3
4.Na2O
Which one will have the highest 2nd ionisation energy?
1.1s2Â 2s2Â 2p6Â 3s1
2. 1s2 2s2 2p4
3.1s2Â 2s2Â 2p6
4.1s2Â 2s2Â 2p6Â 3s2