Fajans rules and ionic character

29 questions on Fajans rules and ionic character from the Chemical Bonding chapter: 5 NEET level, 12 JEE Main, 12 JEE Advanced. Each one opens with its answer and solution.

• Which of the following chlorides has the greatest covalent character? NEET level
• According to Fajans' rules, covalent character in an ionic compound is favoured by NEET level
• Among the lithium halides, the most covalent one is NEET level
• CuCl is more covalent than NaCl although Cu+ and Na+ have similar sizes and the same charge. The reason is that NEET level
• Which of the following hydrogen bonds is the strongest? NEET level
• The correct order of increasing covalent character of the chlorides is JEE Main level
• NaCl dissolves readily in water but AgCl does not. The main reason is that JEE Main level
• Which of the following chlorides has the lowest melting point? JEE Main level
• The correct order of increasing covalent character of silver halides is JEE Main level
• Which of the following carbonates decomposes at the lowest temperature? JEE Main level
• Assertion (A): LiI is more covalent than LiF. Reason (R): I- is larger and more polarisable than F-. JEE Main level
• SnCl4 is a volatile liquid whereas SnCl2 is a solid with a much higher melting point. The best reason is that JEE Main level
• Observed dipole moment and bond length of four gaseous diatomic molecules are: P (3.5 D, 100 pm), Q (9.2 D, 400 pm), R (1.80 D, 92 pm), S (0.82 D, 141 pm). Take... JEE Main level
• Which of the following statements are correct? JEE Main level
• Covalent character of an ionic compound M+X- is favoured by JEE Main level
• Which of the following orders of thermal stability are correct? JEE Main level
• The observed dipole moment of a gaseous diatomic molecule HX is 1.03 D and its bond length is 127 pm. Taking percent ionic character =100xmu_obs/(e d) with e=1.... JEE Main level
• Use ionic potential phi= charge/radius as the measure of polarising power, with radii Na+=102, Ca^2+=100, Li+=76, Mg^2+=72, Al^3+=54 pm. The order of increasing... JEE Advanced level
• Assertion (A): Molten NaCl conducts electricity but molten AlCl3 does not. Reason (R): AlCl3 is covalent because Al^3+ is large and has a low charge. JEE Advanced level
• Li2CO3 decomposes to Li2O and CO2 on moderate heating, whereas Na2CO3 and K2CO3 are stable. The best explanation is that JEE Advanced level
• The correct order of increasing covalent character of MgF2, MgO and Mg3N2 is JEE Advanced level
• A gaseous diatomic molecule XY has a bond length of 160 pm and its bond is 18% ionic. Taking percent ionic character =100xmu_obs/(e d) with e=1.6x10^-19 C and 1... JEE Advanced level
• A gaseous molecule AB has observed dipole moment 6.40 D and bond length 210 pm. With e=1.6x10^-19 C and 1 D=3.336x10^-30 C m, its percent ionic character is clo... JEE Advanced level
• Ionic potential is taken as charge/radius with radii Li+=76, Na+=102, Mg^2+=72, Al^3+=54 and Be^2+=45 pm. Which cation has an ionic potential closest to that of... JEE Advanced level
• Strong heating of MgCl2.6H2O gives MgO (or basic chloride) and HCl instead of anhydrous MgCl2. The underlying reason is that JEE Advanced level
• Use ionic potential phi= charge/radius with radii Li+=76, Na+=102, K+=138, Be^2+=45, Mg^2+=72 and Al^3+=54 pm. Which statements are correct? JEE Advanced level
• Relative to NaCl (m.p. 801 degC), which of the following have a lower melting point mainly because of significant polarisation (covalent character)? JEE Advanced level
• Data for four gaseous diatomics: P (1.10 D, 128 pm), Q (0.80 D, 141 pm), R (9.2 D, 235 pm), S (3.5 D, 170 pm) as (mu_obs, d). Use percent ionic character =100mu... JEE Advanced level
• A gaseous diatomic molecule HX has an observed dipole moment of 1.08 D and its bond is 16.4% ionic. Taking percent ionic character =100xmu_obs/(e d) with e=1.6x... JEE Advanced level