Q$\mathrm{.}1.$ Explain the working principle of a non$-$dispersive infra$-$red analyzer measurement of $CO.$ Write your answer in just $4-5$ bullet points only.

$[$Total$=5$ Marks$]$

Q$\mathrm{.}2.$ What is the relationship between absorbance and transmittance? Express your answer using the mathematical equation. A methylene blue solution shows the transmittance of $60\%$ when taken inside a cell having $2cm$ thickness. If the molar absorption coefficient is $5000\frac{L}{m}o\frac{l^{-1}}{c}m,$ calculate the concentration of the solution.

Total $=5$ Marks$]$

Q$\mathrm{.}3.$ Write the definitions of BOD, COD, and DO$.$ If the BOD measured after $5$ days of a wastewater sample is $150m\frac{g}{L}$ and the reaction rate constant at $20C$ is $0\mathrm{.}2$ per day, compute the ultimate BOD and the BOD remaining in the given sample after $8$ days. Show proper steps by writing the appropriate equations to evaluate your answers. Given, Ultimate BOD$(Lu)=$BOD removed $(Y_t)+$BOD remaining $(L_t)$ Where, BOD remaining at time $t(L_t)=$ Lue ${?}^{-kt}$

$[$Total$=6$ Marks$]$

Q$\mathrm{.}4.$ A reaction $A+BC+D+E$ is taking place inside a continuous stirred tank reactor to produce a pharmaceutical product $($E$)$ as shown in Fig. $1.$ Here, B is the limiting reactant, which is charged to the reactor with a molar flow rate of $1200$kmo$\frac{l}{h}r.$ The exit stream from the reactor has a molar flow rate of $1600$kmo$\frac{l}{h}r,$ which comprises of a mixture of products $C,D,$ and $E$ along with traces of unreacted $A.$ This exit stream goes to a decanter, where $C$ is separated as the bottom product with a molar flow rate of $200$kmo$\frac{l}{h}r$ and the stream S consisting of the remaining components is fed to a distillation column $1($DS$1).$ Reactant A is recovered as the bottom product in DS$-1$ having a molar flow rate of $500$kmo$\frac{l}{h}r.$ The distillate stream marked as $P$ goes to another distillation column $($DS$2),$ which separates $E$ as the final distillate top product with $99\mathrm{.}9\%$ purity and the bottom product flow rate is $100$kmo$\frac{l}{h}r.$

$[$Total$=7$ Marks$]$

$($a$)$ What is the molar flow rate of A$?$ Show the material balance to evaluate your answer.

$[1$ Mark$]$

$($b$)$ Name the components that are present in stream P$.$ Determine the molar flow rates of the streams S$,$ P and, product E$?$ Write the material balance equations to evaluate your answers.

$[4$ Marks$]$

$($c$)12g$ of $CaC{O}_3$ is decomposed to produce $6g$ of CaO from the reaction: $CaC{O}_3$CaO$+C{O}_2.$ Calculate the percentage yield of CaO. Given, atomic weight of calcium $(Ca)$ is $40\frac{g}{m}ol,$ atomic weight of Oxygen $(O)$ is $16\frac{g}{m}ol.$

$[2$ Marks$]$