Ionisation enthalpy

30 questions on Ionisation enthalpy from the Periodic Table and Periodicity chapter: 6 NEET level, 12 JEE Main, 12 JEE Advanced. Each one opens with its answer and solution.

• Which of the following has the highest first ionisation enthalpy? NEET level
• Among the second-period elements Li, Be, B and C, the lowest first ionisation enthalpy is shown by NEET level
• Which element has the largest second ionisation enthalpy? NEET level
• The first ionisation enthalpy of boron is lower than that of beryllium mainly because NEET level
• For any element, the successive ionisation enthalpies follow the order NEET level
• The first ionisation enthalpy of nitrogen is greater than that of oxygen because NEET level
• Using the typical first ionisation enthalpies (Na 496, Mg 738, Al 577, Si 787 in kJ mol^-1), the correct increasing order is JEE Main level
• Sulfur has a slightly lower first ionisation enthalpy (1000 kJ mol^-1) than phosphorus (1012 kJ mol^-1). The best explanation is that JEE Main level
• The species F-, Ne, Na+ and Mg^2+ are isoelectronic. The correct order of the enthalpy needed to remove one electron from each is JEE Main level
• Gallium has a slightly higher first ionisation enthalpy (579 kJ mol^-1) than aluminium (577 kJ mol^-1), contrary to the usual group trend. This is mainly becaus... JEE Main level
• The successive ionisation enthalpies (in kJ mol^-1) of an element X are 738, 1451, 7733 and 10540. The most likely formula of its chloride is JEE Main level
• Using Slater's rules (same-shell electron 0.35, electrons of the n-1 shell 0.85, deeper electrons 1.00), the effective nuclear charge felt by a 3s electron of M... JEE Main level
• Taking the ground-state ionisation energy of hydrogen as 13.6 eV, the energy required to remove the electron from Li^2+ in its ground state is JEE Main level
• The correct increasing order of first ionisation enthalpy for Li, Be, B and C is JEE Main level
• The correct increasing order of first ionisation enthalpy for N, O, F and Ne is JEE Main level
• Select the correct statements about first ionisation enthalpy (typical NCERT values). JEE Main level
• The ionisation enthalpies of Na are Delta_iH_1 = 496 and Delta_iH_2 = 4562 kJ mol^-1; those of Mg are 738 and 1451 kJ mol^-1; Delta_iH_3(Mg) = 7733. Which state... JEE Main level
• Mg atomic mass is taken as 24. The first and second ionisation enthalpies of Mg are 738 and 1451 kJ mol^-1. Calculate the total energy, in kJ, needed to convert... JEE Main level
• An element X has successive ionisation enthalpies (in kJ mol^-1) of 590, 1145, 4912 and 6491. The stable oxide of X and the reason are best given by JEE Advanced level
• Ground-state He+ is to be ionised by a photon. Take the ionisation energy of hydrogen as 13.6 eV and hc = 1240 eV nm. The maximum wavelength of radiation that c... JEE Advanced level
• The first ionisation energy of He is 24.6 eV and that of hydrogen is 13.6 eV. Take 1 eV per atom = 96.485 kJ mol^-1. The total energy to remove both electrons f... JEE Advanced level
• Slater's rules give an effective nuclear charge of 3.50 for the 3p electron of Al and 2.85 for the 3s electron of Mg. Even so, the first ionisation enthalpy of ... JEE Advanced level
• Use Delta_iH_1(Na) = 496 and Delta_iH_2(Mg) = 1451 kJ mol^-1. The enthalpy change for Na(g) + Mg^2+(g) -> Na+(g) + Mg+(g) is JEE Advanced level
• A hydrogen atom in its first excited state (n=2) absorbs a photon of wavelength 100 nm and is ionised. Take hc = 1240 eV nm and the ground-state ionisation ener... JEE Advanced level
• For Mg the ionisation enthalpies are Delta_iH_1 = 738, Delta_iH_2 = 1451 and Delta_iH_3 = 7733 kJ mol^-1. The very large third value arises because JEE Advanced level
• The first ionisation enthalpies (in kJ mol^-1) of the second-period elements are Li 520, Be 899, B 801, C 1086, N 1402, O 1314, F 1681, Ne 2081. Select the corr... JEE Advanced level
• A hypothetical element Y has successive ionisation enthalpies (in kJ mol^-1) 580, 1820, 2750, 11600 and 14800. Select the correct statements. JEE Advanced level
• Select the correct statements about factors affecting ionisation enthalpy. JEE Advanced level
• Taking the ground-state ionisation energy of hydrogen as 13.6 eV, select the correct statements. JEE Advanced level
• The electron in Li^2+ is in the n=2 level. Take the ground-state ionisation energy of hydrogen as 13.6 eV and 1 eV per atom = 96.5 kJ mol^-1. Calculate the ener... JEE Advanced level