The energy of an electron in the ground state of the hydrogen atom is . The ionization enthalpy of atomic hydrogen in terms of J is:
1. 2.81 × 106 J mol
2. 1.31 × 106 J mol
3. 2.31 × 106 J mol
4. 1.81 × 106 J mol
The first ionization enthalpy values (in kJ mol–1) of group 13 elements are :
B | Al | Ga | In | Tl |
801 | 577 | 579 | 558 | 589 |
The explanation for the deviation from the general trend can be -
1. Ga has lower ionization enthalpy than Al.
2. Ga has higher ionization enthalpy than Al.
3. Al has higher ionization enthalpy than Ga.
4. Ga has a lesser valence electron than Al.
An element with higher negative electron gain enthalpy in the given pair is:
(i) O or F (ii) F or Cl
1. O, Cl
2. F, F
3. O, F
4. F, Cl
The basic difference between the electron gain enthalpy (Ea) and electronegativity (EN) is:
1. | Ea is the tendency to lose electrons, while EN is the tendency to repel the shared pairs of electrons. |
2. | Ea is the tendency to gain neutrons, while EN is the tendency to attract the shared pairs of electrons. |
3. | Ea is the tendency to donate electrons, while EN is the tendency to attract the shared pairs of molecules. |
4. | Ea is the tendency to gain electrons, while EN is the tendency to attract the shared pairs of electrons. |
The statement that "the electronegativity of N on the Pauling scale is 3.0 in all the nitrogen
compounds" is incorrect because:
1. | Electronegativity of an element is a variable property. |
2. | Pauling scale is not used to measure electronegativity. |
3. | The electronegativity of N on the Pauling scale is 12.0 |
4. | None of the above. |
The correct statement about the radius of a species is :
1. | Radius increases during cation and anion formation. |
2. | Radius increases during anion formation and decreases during cation formation. |
3. | Radius decreases in cation as well as anion. |
4. | Radius decreases during anion formation and increases during cation formation. |
The values of the first ionization enthalpies for two isotopes would be:
1. | Same. |
2. | Different. |
3. | Same values but positive for the first and negative for the second. |
4. | Same values but negative for the first and positive for the second. |
The reactivity of alkali metals increases, whereas halogen decreases down the group, because:
1. | On moving down, ionization enthalpy decreases in group 1 while the electron gain enthalpy becomes less negative in group 17. |
2. | On moving down, ionization enthalpy increases in group 1 while the electron gain enthalpy becomes less negative in group 17. |
3. | On moving down, ionization enthalpy increases in group 1 while the electron gain enthalpy becomes less positive in group 17. |
4. | On moving down, ionization enthalpy decreases in group 17 while the electron gain enthalpy becomes less negative in group 1. |
The general outer electronic configuration of s, p, d , and f-block elements respectively would be :
1. | ns1-2, nd2np1-6, (n-1)d1-10np0-2, (n-2)f1-14(n-1)d0-10ns2 |
2. | ns1-2, ns2np1-6, (n-1)f1-10ns0-2, (n-2)g1-14(n-1)d0-1ns2 |
3. | ns1-2, ns2np1-6, (n-1)d1-10ns1-2, (n-2)f1-14(n-1)d0-1 ns2 |
4. | np1-2, nd2np1-6, (n-1)d1-10ns0-2, (n-2)f1-14(n-1)d0-10ns2 |
The position of elements with an outer electronic configuration as
1. 6th period and 10th group.
2. 7th period and 3rd group.
3. 6th period and 3rd group.
4. 7th period and 9th group.