Q. No.
The ionic radii (in Å) of the isoelectronic species \(\mathrm{N^{3-}}, \mathrm{O^{2-}}, and~ \mathrm{F^-}\) are respectively:
1. 1.36, 1.40 and 1.71
2. 1.36, 1.71 and 1.40
3. 1.71, 1.40 and 1.36
4. 1.71, 1.36 and 1.40
The correct sequence which shows decreasing order of the ionic radii of the elements is:
1. O2− > F− > Na+ > Al3+
2. Al3+ > Mg2+ > Na+ > F− > O2−
3. Na+ > Mg2+ > Al3+ > O2− > F−
4. Na+ > F− > Mg2+ > O2− > Al3+
The set that contains atomic numbers of only transition elements is:
1. 21, 32, 53, 64
2. 9, 17, 34, 38
3. 21, 25, 42, 72
4. 37, 42, 50, 64
Find the correct increasing order of ionic radii for the following isoelectronic species:
N³⁻, O²⁻, F⁻, Na⁺, Mg²⁺ and Al³⁺
1. Al³⁺ < Na⁺ < Mg²⁺ < O²⁻ < F⁻ < N³⁻2. N³⁻ < O²⁻ < F⁻ < Na⁺ < Mg²⁺ < Al³⁺
3. Al³⁺ < Mg²⁺ < Na⁺ < F⁻ < O²⁻ < N³⁻
4. N³⁻ < F⁻ < O²⁻ < Mg²⁺ < Na⁺ < Al³⁺
The group number, number of valence electrons, and valency of an element with atomic number 15, respectively, are:
1. 16, 6 and 3
2. 15, 6 and 12
3. 16, 5 and 2
4. 15, 5 and 3
The formula of a compound that is formed by the Aluminium and Sulphur is:
| 1. | AlS2 | 2. | Al2S3 |
| 3. | Al3S2 | 4. | Al3S4 |
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The IUPAC name and symbol for the element with atomic number 120 are respectively:
1. Unnilbium; Ubn
2. Unbinilium; Ubn
3. Ununbium; Uub
4. Unbinilium; Uub
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In which of the following arrangements the order is not according to the property indicated against it?
| 1. | Li < Na < K < Rb : Increasing metallic radius |
| 2. | I < Br < F < Cl: Increasing electron gain enthalpy (with negative sign) |
| 3. | B < C < N < O: Increasing first ionisation enthalpy |
| 4. | Al3+ < Mg2+ < Na+ < F- : Increasing ionic size |
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