Chemistry NCERT Exemplar Solutions Class 11th Chapter Eight

$6.023*{10}^{22}$ molecules are present in $10\mathrm{g}$ of a substance '  $x$ '. The molarity of a solution containing $5\mathrm{g}$  of substance ' $\mathrm{x}$  ' in   $2\mathrm{L}$ solution is $*{10}^{-3}$ .                 

An acidic solution of dichromate is electrolyzed for 8 minutes using $2\mathrm{A}$  current. As per the following equation ${\mathrm{C}\mathrm{r}}_2{\mathrm{O}}_7^{2-}+14{\mathrm{H}}^{+}+6{\mathrm{e}}^{-}\to 2{\mathrm{C}\mathrm{r}}^{3+}+7{\mathrm{H}}_2\mathrm{O}$   . The amount of ${\mathrm{C}\mathrm{r}}^{3+}$ obtained was $0.104\mathrm{g}$   . The efficiency of the process (in %) is (Take: $\mathrm{F}=96000\mathrm{C}$   , At. Mass of chromium $=52$    )

If   $250{\mathrm{c}\mathrm{m}}^3$ of an aqueous solution containing $0.73\mathrm{g}$ of a protein $\mathrm{A}$  is isotonic with one litre of another aqueous solution containing $1.65\mathrm{g}$  of a protein $\mathrm{B}$ , at $298\mathrm{K}$ , the ratio of the molecular masses $A$ of  and $B$  is   $*{10}^{-2}$ (to the nearest integer). 

The number of  $\mathrm{C}=\mathrm{O}$ groups present in a tripeptide Asp - Glu - Lys is

The volume (in  $\mathrm{m}\mathrm{L}$ ) of $0.1\mathrm{N}\mathrm{N}\mathrm{a}\mathrm{O}\mathrm{H}$  required to neutralise $10\mathrm{m}\mathrm{L}$ of $0.1\mathrm{N}$  phosphinic acid is

Gaseous cyclobutene isomerizes to butadiene in a first order process which has 'k' value of 3.3 * 10^-4 s^-1 at 153°C. The time in minutes it takes for the isomerization to proceed 40% to completion at this temperature is______ (Rounded off the nearest integer)

The coordination number of an atom in a body- centred cubic structure is___________.

 [Assume that the lattice is made up of atoms]

A proton and a Li³⁺ nucleus are accelerated by the same potential. If ${\lambda }_{Li}and{\lambda }_P$  denote the de Brogle wavelength of Li³⁺ and proton respectively, then the value of $\frac{{\lambda }_{Li}}{{\lambda }_P}isx*10^{-1}.$  The value of x is_________ (Rounded off to the nearest integer)           [Mass of Li³⁺ = 8.3 mass of proton]

4.5g of compound A (MW = 90) was used to make 250 mL of its aqueous solution. The molarity of the solution in M is * 10^-1. The value of x is_________ (Rounded off to the nearest integer)

The reaction of sulphur in alkaline medium is given below

$S_{8\left(s\right)}+aO{H^{-}}_{\left(aq\right)}\to b{S^{2-}}_{\left(aq\right)}+c{S}_2{O_3^{2-}}_{\left(aq\right)}+d{H}_2{O}_{\left(I\right)}$            

The values of 'a' is____________. (Integer answer)