Recent questions tagged process-calculations-and-thermodynamics

The molar excess Gibbs free energy $(g^{E})$ of a liquid mixture of $A$ and $B$ is given by $$\frac{g^{E}}{RT} = x_{A}x_{B}\left [ C_{1} + C_{2} \left ( x_{A} - x_{B} \ri...

For a pure substance, the following data at saturated conditions are given:$$\begin{array}{cccc}\text{ln}\:{P^{\text{sat}} (\text{bar})} & \text{T (K)} \\ 0.693 & 350 \\ ...

Consider the process flowsheet in the figure. An irreversible liquid-phase reaction $A \rightarrow B$ (reaction rate $-r_{A} = 164 \:x_{A}\text{ kmol }m^{-3}\:h^{-1}$) oc...

Two reservoirs located at the same altitude are connected by a straight horizontal pipe of length $120\:m$ and inner diameter $0.5\:m$, as shown in the figure. A pump tra...

A single-effect evaporator with a heat transfer area of $70\:m^{2}$ concentrates a salt solution using steam. The salt solution feed rate and temperature are $10000\:kg\:...

An equimolar binary mixture is to be separated in a simple tray-distillation column. The feed rate is $50\text{ kmol min}^{-1}$ . The mole fractions of the more volatile ...

The dry-bulb temperature of air in a room is $30^{\circ}C$. The Antoine equation for wateris given as $$\text{ln} P^{sat} = 12.00 -\frac{4000}{T - 40}$$ where $T$ is the ...

Information for a proposed greenfield project is provided in the table. The discounted cash flow for the fourth year is Rs ___________________ crores (rounded off to one ...

Consider the process in the figure. The liquid phase elementary reactions $$A + B \rightarrow P \:\:\:\: -r_{B1} = k_{1}\:x_{A}\:x_{B}$$ $$P + B \rightarrow S \:\:\:\: -r...

An elementary irreversible liquid-phase reaction, $2A \rightarrow B$, is carried out under isothermal conditions in a $1\:m^{3}$ ideal plug flow reactor $\text{(PFR)}$ as...

An elementary irreversıble gas-phase reaction, $A \rightarrow B + C$, is carried out at fixed temperature and pressure in two separate ideal reactors: $(i)$ a $10\:m^{3}$...

In a double-pipe heat exchanger of $10 \: m$ length, a hot fluid flows in the annulus and a cold fluid flows in the inner pipe. The temperature profiles of the hot $(T_h)...

For a shell-and-tube heat exchanger, the clean overall heat transfer coefficient is calculated as $\text{250 W m$^{-2}$ K}^{-1}$ for a specific process condition. It is e...

In reverse osmosis, the hydraulic pressure and osmotic pressure at the feed side of the membrane are $P_1$ and $\pi_1$, respectively. The corresponding values are $P_2$ a...

A principal amount is charged a nominal annual interest rate of $10 \%$. If the interest rate is compounded continuously, the final amount at the end of the one year woul...

A source placed at the origin of a circular sample holder (radius $r=1 \: m$) emits particles uniformly in all directions. A detector of length $l=1 \: cm$ has been place...

The van der Waals equation of the state is given by$$P_r = \dfrac{8T_r}{3v_r-1} – \dfrac{3}{v_r^2}$$where $P_r$, $T_r$ and $v_r$ represent reduced pressure, reduced tempe...

Consider a steady flow of an incompressible, Newtonian fluid through a smooth circular pipe. Let $\alpha_{\textit{laminar}}$ and $\alpha_{\textit{turbulent}}$ denote the ...

The molar heat capacity at constant pressure $C_p$ (in $\text{J mol}^{-1} K^{-1}$) for $n$-pentane as a function of temperature $(T$ in $K)$ is given by$ \dfrac{C_p}{R} =...

The following homogeneous liquid phase reactions are at equilibrium,The values of rate constants are given by: $k_1 = 0.1 s^{-1}$, $k_{-1}=0.2 s^{-1}, k_2 = 1 s^{-1}, k_{...

In a solvent regeneration process, a gas is used to strip a solute from a liquid in a countercurrent packed tower operating under isothermal condition. Pure gas is used i...

Formaldehyde is produced by the oxidation of methane in a reactor. The following two parallel reactions occur.$$CH_4+O_2 \rightarrow HCHO+H_2O \\ CH_4 +2O_2 \rightarrow C...

The combustion of carbon monoxide is carried out in a closed, rigid and insulated vessel. $1 \text{ mol}$ of $CO$, $0.5 \text{ mol}$ of $O_2$ and $2 \text{ mol}$ of $N_2$...

A gaseous mixture at $1$ bar and $300 \: K$ consists of $20 \text{ mol } \% \: CO_2$ and $80 \text{ mol } \%$ inert gas.Assume the gases to be ideal. Take $R=8.314 \text{...

A binary liquid mixture consists of two species $1$ and $2$. Let $\gamma$ and $x$ represent the activity coefficient and the mole fraction of the species, respectively. U...

Seawater is passed through a column containing a bed of resin beads.Density of seawater $=1025 \: \text{ kg m}^{-3}$Density of resin beads $=1330 \text{ kg m}^{-3}$Diame...

A double-effect evaporator is used to concentrate a solution. Steam is sent to the first effect at $110\:^{\circ} C$ and the boiling point of the solution in the second e...

Consider a solid slab of thickness $2L$ and uniform cross section $A$. The volumetric rate of heat generation within the slab is $\dot{g} \: (W \: m^{-3})$. The slab lose...

A distillation column handling a binary mixture of $A$ and $B$ is operating at total reflux. It has two ideal stages including the reboiler. The mole fraction of the more...

In a batch drying experiment, a solid with a critical moisture content of $0.2 \: kg$ $H_2O/kg$ dry solid is dried from an initial moisture content of $0.35 \: kg$ $H_2O/...

As shown in the figure below, air flows in parallel to a freshly painted solid surface of width $10 \: m$, along the $z$-direction.The equilibrium vapor concentration of ...

The following isothermal autocatalytic reaction $$ A +B \longrightarrow 2B \quad\quad\quad(-r_A)=0.1C_AC_B(\text{mol } L^{-1} s^{-1})$$is carried out in an ideal continuo...

Reactant $A$ decomposes to products $B$ and $C$ in the presence of an enzyme in a well-stirred batch reactor. The kinetic rate expression is given by$$-r_A = \dfrac{0.01C...

The following homogeneous, irreversible reaction involving ideal gases, $$A \longrightarrow B+C \quad\quad\quad(-r_A)=0.5C_A (\text{mol L}^{-1} s^{-1})$$ is carried out i...

Operating labor requirements $L$ in the chemical process industry is described in terms of the plant capacity $C ( \text{kg day}^{-1})$ over a wide range $(10^3-10^6)$ by...

A viscous liquid is pumped through a pipe network in a chemical plant. The annual pumping cost per unit length of pipe is given by $$C_{\text{pump}} = \dfrac{48.13\: q^2 ...

An irreversible gas phase reaction $2 \textbf{P} \rightarrow 4 \textbf{Q} + \textbf{R}$ is conducted in an isothermal and isobaric batch reactor. Assume ideal gas behavio...

Consider two Carnot engines $C_1$ and $C_2$ as shown in the figure.The efficiencies of the engines $C_1$ and $C_2$ are $0.40$ and $0.35$, respectively. If the temperature...

The decomposition of acetaldehyde $(X)$ to methane and carbon monoxide follows four-step free radical mechanism. The overall rate of decomposition of $X$ is $$-r_X=k_2 \b...