Effect of Nuclear Charge

Q.

What is the formula for calculating no of lone pairs of any compound?

Q.

The radius of a calcium ion is 94 pm and of an oxide ion is 146 pm. Predict the crystal structure of calcium oxide.

1. ZnS structure

2. CaF₂ structure

3. CsCl structure

4. NaCl structure

Q.

Which of the following orders of ionic radii is correctly represented?

1. $H^{-}>H^{+}>H$

2. $N{a}^{+}>F^{-}>O^{2-}$

3. $O^{2-}>F^{-}>N{a}^{+}$

4. $A{l}^{3+}>M{g}^{2+}>N^{3-}$

Q.

Select The Correct Order Of Ionic Radii For${\mathrm{Na}}^{+},{\mathrm{Mg}}^{2+},{\mathrm{F}}^{-}\mathrm{and}{\mathrm{O}}^{2-}$?

1. ${\mathrm{Mg}}^{2+}<{\mathrm{Na}}^{+}<{\mathrm{F}}^{-}<{\mathrm{O}}^{2-}$

2. ${\mathrm{Na}}^{+}<{\mathrm{Mg}}^{2+}<{\mathrm{F}}^{-}<{\mathrm{O}}^{2-}$

3. ${\mathrm{O}}^{2-}<{\mathrm{F}}^{-}<{\mathrm{Na}}^{+}<{\mathrm{Mg}}^{2+}$

4. ${\mathrm{Mg}}^{2+}<{\mathrm{O}}^{2-}<{\mathrm{Na}}^{+}<{\mathrm{F}}^{-}$

Q.

${\mathrm{Na}}^{+}$ is smaller than $\mathrm{Na}$ atom because:

Q.

The bromine atom possesses 35 electrons. It contains 6 electrons in 2p orbital, 6 electrons in 3p orbital and 5 electrons in 4p orbital. Which of these electron experiences the lowest effective nuclear charge?

Q.

Which one of the following ions will be smallest in size?

1. $N{a}^{+}$

2. $O^{2-}$

3. $M{g}^{2+}$

4. $F^{-}$

Q.

Ionic radii are

1. Inversely proportional to effective nuclear charge

2. Inversely proportional to square of effective nuclear charge.

3. Directly proportional to effective nuclear charge

4. Directly proportional to square of effective nuclear charge

Q.

The bromine atom possesses 35 electrons. It contains 6 electrons in 2p orbital, 6 electrons in 3p orbital and 5 electrons in 4p orbital. Which of these electron experiences the lowest effective nuclear charge?

Q.

What are the similarities and differences between 1s and 2s orbital?

Q.

Arrange Se^2-, I^-, Br^-, O^2- and F^- in decreasing order of their ionic radius.

Q.

Ionic species are stabilized by the dispersal of charge. Which of the following carboxylate ion is the most stable?

1. 
2. 
3. 
4. 

Q.

Question 22

Arrange s, p and d subshells of a shell in the increasing order of effective nuclear charge $\left(Z_{eff}\right)$ experienced by the electron present in them.

Q.

In which of the following compounds the carbon marked with asterisk is expected to have greatest positive charge?

1. ${}^{\ast }C{H}_3-C{H}_2-Br$
2. ${}^{\ast }C{H}_3-C{H}_2-C{H}_3$
3. ${}^{\ast }C{H}_3-C{H}_2-M{g}^{+}C{l}^{-}$

4. ${}^{\ast }C{H}_3-C{H}_2-Cl$

Q. What is inert pair effect ?

Q.

The correct order of the ionic radii of ${\mathrm{O}}^{2-}$, ${\mathrm{N}}^{3-}$, ${\mathrm{F}}^{-}$, ${\mathrm{Mg}}^{2+}$, ${\mathrm{Na}}^{+}$ and${\mathrm{Al}}^{3+}$ is:

1. ${\mathrm{N}}^{3-}<{\mathrm{O}}^{2-}<{\mathrm{F}}^{-}<{\mathrm{Na}}^{+}<{\mathrm{Mg}}^{2+}<{\mathrm{Al}}^{3+}$

2. ${\mathrm{N}}^{3-}<{\mathrm{F}}^{-}<{\mathrm{O}}^{2-}<{\mathrm{Mg}}^{2+}<{\mathrm{Na}}^{+}<{\mathrm{Al}}^{3+}$

3. ${\mathrm{Al}}^{3+}<{\mathrm{Na}}^{+}<{\mathrm{Mg}}^{2+}<{\mathrm{O}}^{2-}<{\mathrm{F}}^{-}<{\mathrm{N}}^{3-}$

4. ${\mathrm{Al}}^{3+}<{\mathrm{Mg}}^{2+}<{\mathrm{Na}}^{+}<{\mathrm{F}}^{-}<{\mathrm{O}}^{2-}<{\mathrm{N}}^{3-}$

Q. As per Pauling, the radius of an isoelectronic ion in a given crystal is inversely proportional to the effective nuclear charge, $Z^{\ast }$.
$Z^{\ast }=Z-\sigma$; where $\sigma$ represents the screening constant. The crystal structure of $\text{NaF}$ is shown as below :

The radius of $F^{-}$ in pm is $(130+x)$ . The value of $x$ in nearest possible integer is

Q. Cations are present in the interstitial sites in _________.

1. Schottky defect
2. Frenkel defect
3. Vacancy defect
4. Metal deficiency defect

Q. Can spin quantum number of an orbital be equal to zero? Does spin quantum number equal to zero mean that no electron present in that particular orbital

Q. The reason(s) for small radius of $Ga$ compared to $Al$ is/are :

1. poor screening effect of d orbitals.
2. decrease in nuclear charge
3. presence of higher orbital
4. higher atomic number

Q.

Identify the correct order of the size of the following. [CBSE AIPMT 2007]

1. $C{a}^{2+}<K^{+}<Ar<C{l}^{-}<S^{2-}$

2. $Ar<C{a}^{2+}<K^{+}<C{l}^{-}<S^{2-}$

3. $C{a}^{2+}<K^{+}<Ar<S^{2-}<C{l}^{-}$

4. $C{a}^{2+}<Ar<K^{+}<C{l}^{-}<S^{2-}$

Q.

Explain the term inert pair effect ?

Q. Arrange the following elements in the increasing order of electronegativity.

1. $C,N,Si,P$
2. $N,Si,C,P$
3. $P,Si,N,C$
4. $Si,P,C,N$

Q.

Which one of the following is the smallest in size?

1. $N{a}^{3+}$

2. $O^{2-}$

3. $F^{-}$

4. $N{a}^{+}$

Q.

Which of the following factor does not affect the atomic size of d block elements?

1. Number of shielding electrons

2. Number of protons in nucleus

3. Number of neutrons in nucleus

4. Electrostatic attraction between nucleus and outermost electrons.

Q.

What does atomic radius and ionic radius really mean to you?

Q. Assertion :Fluorine has a less negative electron affinity than chlorine. Reason: There is the relatively greater effectiveness of $2p-$electrons in the small $F$atom to repel the additional electron entering the atom than to $3p-$electrons in the larger $Cl$ atom.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Assertion is incorrect but Reason is correct

Q.

Which one of the following is the smallest cation?

1. $N{a}^{+}$

2. $M{g}^{2+}$

3. $C{a}^{2+}$

4. $A{l}^{3+}$

Q. When an extra cation and electron occupies the interstitital sites in its crystal lattice, it is called:

1. Schottky defect
2. Metal excess defect
3. Stoichiometric defect
4. Frenkel defect

Q.

The size of isoelectronic species — F^–, Ne and Na⁺ is affected by

(a) Nuclear charge (Z )

(b) Valence principal quantum number (n)

(c) Electron-electron interaction in the outer orbitals

(d) None of the factors because their size is the same.