Which of the following expressions is correct in case of a \( \mathrm{CsCl} \) unit cell (edge length ‘\( a \)’)?
\( r_{\mathrm{Cs}^{+}} + r_{\mathrm{Cl}^{-}} = \dfrac{\sqrt{3}}{2}\, a \)
\( r_{\mathrm{Cs}^{+}} + r_{\mathrm{Cl}^{-}} = a \)
\( r_{\mathrm{Cs}^{+}} + r_{\mathrm{Cl}^{-}} = \dfrac{a}{2} \)
\( r_{\mathrm{Cs}^{+}} + r_{\mathrm{Cl}^{-}} = \dfrac{a}{\sqrt{2}} \)
The correct relationships between unit cell edge length '\( a \)' and radius of sphere '\( r \)' for face-centred and body–centred cubic structures respectively are:
A metal \( \mathrm{M} \) forms hexagonal close-packed structure. The total number of voids in \( 0.02 \) mol of it is ______ \( \times 10^{21} \) (Nearest integer).(Given \( N_A = 6.02 \times 10^{23} \) )
The number of species having a square planar shape from the following is __________ .\( \mathrm{XeF_4}, \, \mathrm{SF_4}, \, \mathrm{SiF_4}, \, \mathrm{BF_4^-}, \, \mathrm{BrF_4^-}, \, [\mathrm{Cu(NH_3)_4}]^{2+}, \, [\mathrm{FeCl_4}]^{2-}, \, [\mathrm{PtCl_4}]^{2-} \)
When \( \mathrm{Fe_{0.93}O} \) is heated in presence of oxygen, it converts to \( \mathrm{Fe_2O_3} \). The number of correct statement/s from the following is \( \_\_\_\_\_ \). I. The equivalent weight of \( \mathrm{Fe_{0.93}O} \) is \( \dfrac{\text{Molecular weight}}{0.79} \) II. The number of moles of \( \mathrm{Fe^{2+}} \) and \( \mathrm{Fe^{3+}} \) in \( 1 \) mole of \( \mathrm{Fe_{0.93}O} \) is \( 0.79 \) and \( 0.14 \) respectively III. \( \mathrm{Fe_{0.93}O} \) is metal deficient with lattice comprising of cubic closed packed arrangement of \( \mathrm{O^{2-}} \) ions IV. The \( \% \) composition of \( \mathrm{Fe^{2+}} \) and \( \mathrm{Fe^{3+}} \) in \( \mathrm{Fe_{0.93}O} \) is \( 85\% \) and \( 15\% \) respectively
A sample of metal oxide has formula \( \mathrm{M_{0.83}O_{1.00}} \). The metal M can exist in two oxidation states \( +2 \) and \( +3 \). In the sample of \( \mathrm{M_{0.83}O_{1.00}} \), the percentage of metal ions existing in \( +2 \) oxidation state is ______ \( \% \). (Nearest integer)
A metal \( \mathrm{M} \) crystallizes into two lattices: face centred cubic \( (\mathrm{fcc}) \) and body centred cubic \( (\mathrm{bcc}) \) with unit cell edge length of \( 2.0 \) and 2.5 Å respectively. The ratio of densities of lattices fcc to bcc for the metal \( \mathrm{M} \) is ______. \([\text{Nearest integer}]\)
An atomic substance A of molar mass \( 12 \, \text{g mol}^{-1} \) has a cubic crystal structure with edge length of \( 300 \, \text{pm} \). The no. of atoms present in one unit cell of A is ________ . (Nearest integer) Given the density of A is \( 3.0 \, \text{g mL}^{-1} \) and \( N_A = 6.02 \times 10^{23} \, \text{mol}^{-1} \)
A cubic solid is made up of two elements X and Y. Atoms of X are present on every alternate corner and one at the center of cube. Y is at \( 1/3 \) rd of the total faces. The empirical formula of the compound is:
