A metal M crystallizes into two lattices :- face centred cubic (fcc) and body centred cubic (bcc) with unit cell edge length of $2.0$ and $2.5\,\mathop A\limits^o$ respectively. The ratio of densities of lattices fcc to bcc for the metal M is ____________. (Nearest integer)

Sodium metal crystallizes in a body centred cubic lattice with unit cell edge length of $4~\mathop A\limits^o$. The radius of sodium atom is __________ $\times ~10^{-1}$ (Nearest integer)

An atomic substance A of molar mass $12 \mathrm{~g} \mathrm{~mol}^{-1}$ has a cubic crystal structure with edge length of $300 ~\mathrm{pm}$. The no. of atoms present in one unit cell of is ____________. (Nearest integer)

The distance between Na⁺ and Cl^$-$ ions in solid NaCl of density 43.1 g cm^$-$3 is _______________ $\times$ 10 m. (Nearest Integer)

$2 \mathrm{MnO}_4^{-}+\mathrm{bI}^{-}+\mathrm{cH}_2 \mathrm{O} \rightarrow x \mathrm{I}_2+y \mathrm{MnO}_2+z \overline{\mathrm{O}} \mathrm{H}$

Total number of acidic oxides among

$\mathrm{N_2O_3,NO_2,N_2O,Cl_2O_7,SO_2,CO,CaO,Na_2O}$ and is ____________.

The density of a monobasic strong acid (Molar mass 24.2 g/mol) is 1.21 kg/L. The volume of its solution required for the complete neutralization of 25 mL of 0.24 M NaOH is __________ $\times$ 10$^{-2}$ mL (Nearest integer)

In the estimation of bromine, 0.5 g of an organic compound gave 0.40 g of silver bromide. The percentage of bromine in the given compound is _________ % (nearest integer)

(Relative atomic masses of Ag and Br are 108u and 80u, respectively).

0.25 g of an organic compound containing chlorine gave 0.40 g of silver chloride in Carius estimation. The percentage of chlorine present in the compound is ___________. [in nearest integer]

(Given : Molar mass of Ag is 108 g mol^$-$1 and that of Cl is 35.5 g mol^$-$1)

Metal $\mathrm{M}$ crystallizes into a fcc lattice with the edge length of $4.0 \times 10^{-8} \mathrm{~cm}$. The atomic mass of the metal is ____________ . (Nearest integer)

0.2 g of an organic compound was subjected to estimation of nitrogen by Dumas method in which volume of N₂ evolved (at STP) was found to be 22.400 mL. The percentage of nitrogen in the compound is _________. [nearest integer]

(Given : Molar mass of N₂ is 28 g mol^$-$1. Molar volume of N₂ at STP : 22.4 L)

1 mole of $\mathrm{PbS}$ is oxidised by "$\mathrm{X}$" moles of $\mathrm{O}_3$ to get "" moles of . _________.

An organic compound with 51.6% sulfur is heated in a Carius tube. The amount of this compound which will form 0.752 g of barium sulphate is ___________ $\times$ 10^$-$1 g.

(Given molar mass of barium sulphate 233 g mol^$-$1) (Nearest integer).