Coordination and Oxidation Number

Q. 23 How to find hybridization for chromium ions in chromate and dichromate?

Q. The number of lone pair present in N-atom in NH4+ ion is

Q. 41. Al3+ replaces Na+ ions at edge centres of NaCl structure.Calculate vacancies in 1mole NaCl.

Q. In which of the following complexes, nickel is in the highest oxidation state?

1. $K_4\left[Ni\right(CN{)}_4]$
2. $\left[K_{2}Ni{F}_6\right]$
3. $\left[Ni\right(CO{)}_4]$
4. $\left[Ni\right(CN{)}_4{]}^{2-}$

Q. The radius ratio of Cs+ to Cl- is 0.90. If the radius of Cl- ion is 1.80 angstrong, the false statement regarding the CsCl structure is-1)the dis†an ce between the centres of Cl- ions is greater than 3.60angstrong, 2)dis†an ce between the centres of two Cl- ions is 3.60angstrong, 3)dis†an ce between Cs+ion and Cl-ion is 3.42angstrong, 4)dis†an ce between two Cs+ ions is 3.24angstrong.

Q. 12.A mixture of KBr and NaBr weighing 0.560 gm was treated With aqueous Ag+ and all the bromide ion was recovered as 00.97 gm of pure AgBr.The weight of KBr in the sample is: A)0.25 gm B)0.212 gm C)0.36 gm D)0.285 gm

Q. 9. What are the final concentrations of all the ions when following are mixed? 50 mL of 0.12 A/ Fe(N03 ) 3 , 100 mL of 0.10A/FeCl3 and 100 mL of 0.26M Mg(N03)2 .

Q. 30.Which of the following statement is correct for csbr3? A) it is a covalent sold b) it contain cs+3 and br- c) it contain cs+ and br3-ion. D) it contain cs+, br- ions.

Q. In the $ZnS$ (Zinc Blende) structure, what would be the distance for the nearest cation $\left(Z{n}^{2+}\right)$ from an anion $\left(S^{2-}\right)$ ?
Here $a$ is the edge cell length.

1. $\sqrt{2}a$
2. $\frac{\sqrt{3}a}{4}$
3. $\frac{a}{4}$
4. $a$

Q. Which of the following ions forms a hydroxide highly soluble in water?

1. $N{a}^{2+}$
2. $K^{+}$
3. $Z{n}^{2+}$
4. $A{l}^{3+}$

Q.

what is the skeletal structure of the atom?

Q. 81) lonisation constant of CH3COOH is 1.7 x 10-5 andconcentration of H ions is 3.4 x 10-4. Then find out initial concentration of CH2COOH moleculesnc3.4 x 104 K(3) 6.8 x 10-4(2) 3.4 x 10-3(4) 6.8 x 10-3

Q. How hydration enthalpy is related to atomization enthalpy?

Q. A six-coordinate complex of formula $CrC{l}_6.6H_2$O is green in colour. A $0.1\text{M}$ solution of the complex when treated with excess of $AgN{O}_3$ gave $28.7\text{g}$ of white precipitate. The formula of the complex would be:

1. $\left[Cr{\left(H_{2}O\right)}_6\right]C{l}_3$
2. $\left[Cr{\left(H_{2}O\right)}_{5}Cl\right]C{l}_2.H_{2}O$
3. $\left[Cr\right(H_{2}O{)}_{4}C{l}_2]Cl.2H_{2}O$
4. $\left[Cr{\left(H_{2}O\right)}_{3}C{l}_3\right].3H_{2}O$