Q. No.1st (∆H1) and 2nd (∆H2) Ionization Enthalpies (in kJ mol–1) and the (∆egH) Electron Gain Enthalpy (in kJ mol–1) of a few elements are given below:
Elements
ΔH1
ΔH2
ΔegH
I
520
7300
–60
II
419
3051
–48
III
1681
3374
–328
IV
1008
1846
–295
V
2372
5251
+48
VI
738
1451
–40
The most reactive metal is:
1.
VI
2.
III
3.
I
4.
II
The formula of the stable binary compounds that would be formed by an element having atomic number 71 and fluorine:
1. LuF6
2. LuF2
3. LuF3
4. LuF4
The factor that does not affect the valence electron is:
| 1. | Azimuthal quantum number |
| 2. | Nuclear charge (Z) |
| 3. | Nuclear mass |
| 4. | Number of core electrons |
The size of isoelectronic species: F–, Ne and Na+, is affected by :
| 1. | Nuclear charge (Z) |
| 2. | Valence principal quantum number (n) |
| 3. | Electron-electron interaction in the outer orbitals |
| 4. | None of the above factors because their size is the same |
The incorrect statement about ionization enthalpy is:
| 1. | Ionization enthalpy increases for each successive electron. |
| 2. | Noble gases have the highest ionization enthalpy. |
| 3. | A big jump in ionization enthalpy indicates a stable configuration. |
| 4. | Ionization enthalpy of oxygen is higher than that of nitrogen. |
The ionic radii vary in :
| (a) | Inverse proportion to the effective nuclear charge. |
| (b) | Inverse proportion to the square of effective nuclear charge. |
| (c) | Direct proportion to the screening effect. |
| (d) | Direct proportion to the square of screening effect. |
Choose the correct option :
1. (a), (c)
2. (b), (c)
3. (c), (d)
4. (b), (d)
Match the following isoelectronic species in Column I and Column II:
| Column I | Column II | ||
| i. | a. | ||
| ii. | Ar | b. | |
| iii. | c. | ||
| iv. | d. |
| i | ii | iii | iv | |
| 1. | b | c | a | d |
| 2. | c | b | a | d |
| 3. | c | d | b | a |
| 4. | b | c | d | a |
The correct order of ionization energy of W, X, Y and Z is-
| 1. | W > X > Y > Z | 2. | W < X < Y > Z |
| 3. | W < X > Y< Z | 4. | W > X > Y< Z |
Consider the following curves:
X represents group with highest atomic radius. The element that belongs to Y group can be :
| 1. | Na | 2. | Mg |
| 3. | Br | 4. | Si |
In the following graph of variation of ionization energy with atomic number, X, Y, and Z represent elements.
The group number of X, Y, and Z elements is:
| 1. | 1st group | 2. | 15th group |
| 3. | 17th group | 4. | 18th group |
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