The ions O2–, F–, Na+, Mg2+, and Al3+ are isoelectronic. Their ionic radii show:
1. | A significant increase from O2– to Al3+. |
2. | A significant decrease from O2– to Al3+. |
3. | An increase from O2– to F– and then a decrease from Na+ to Al3+. |
4. | A decrease from O2– to F– and then an increase from Na+ to Al3+. |
The period and group number of the element with Z =114 are:
1. | 8th period and 16th group | 2. | 7th period and 14th group |
3. | 14th period and 7th group | 4. | 9th group and 14th period |
The trend of atomic radius in a period and a group is :
1. | Generally decreases from right to left across a period and increases down a group. |
2. | Generally increases from left to right across a period and decreases down a group. |
3. | Generally decreases from left to right across a period and increases down a group. |
4. | Generally remains same from left to right across a period and increases down a group. |
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 general outer electronic configuration of s, p, d , and f-block elements respectively would be :
1. | ns1-2, ns2np1-6, (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)f1-14nd0-1ns2 |
3. | ns1-2, ns2np1-6, (n-1)d1-10ns1-2, (n-2)f1-14(n-1)d0-1 ns2 |
4. | ns1-2, ns2np1-6, (n-1)d1-10ns0-2, (n-2)f1-14(n-2)d0-10ns2 |
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 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. |
Among the following, the elements that can show covalency greater than 4 is/are:
(a) Be
(b) P
(c) S
(d) B
Choose the correct option
1. (a), (d)
2. (b), (c)
3. (c), (d)
4. (b), (d)