Methane $(CH_4)$ at $25^\circ C,$ 1 atm enters a furnace operating at steady state and burns completely with 140% of theoretical air entering at 400 K, 1 atm. The products of combustion exit at 700 K, 1 atm. Kinetic and potential energy effects are negligible. If the rate of heat transfer from the furnace to the surroundings is 400 kW, determine the mass flow rate of methane, in kg/s.

Methane $\left(\mathrm{CH}_4\right)$ at $25^{\circ} \mathrm{C}, 1 \mathrm{~atm}$ enters a furnace operating at steady state and burns completely with $140 \%$ of theoretical air entering at $400 \mathrm{~K}, 1\ \text{atm}$. The products of combustion exit at $700 \mathrm{~K}, 1 \mathrm{~atm}$. Kinetic and potential energy effects are negligible. If the rate of heat transfet from the furnace to the surroundings is $400 \mathrm{~kW}$, determine the mass flow rate of methane, in $\mathrm{kg} / \mathrm{s}$.

Find the amount. $$ \begin{matrix}\mathrm{\scriptstyle{Product \ description}} & \mathrm{\scriptstyle{Unit \ price}} & \mathrm{\scriptstyle{Number}} & \mathrm{\scriptstyle{Subtotal}} & \mathrm{\scriptstyle{Tax (8\text{\\%})}} & \mathrm{\scriptstyle{Total}}\\\mathrm{\scriptstyle{Notebooks \ (2 \ pack)}} & \mathrm{$1.99} & \text{2} & \mathrm{$3.98}\\\end{matrix} $$

Make a copy of the isothermal transformation diagram for a 1.13 wt% C iron–carbon alloy, and then on this diagram sketch and label time–temperature paths to produce the following microstructures: (a) 6.2% proeutectoid cementite and 93.8% coarse pearlite (b) 50% fine pearlite and 50% bainite (c) 100% martensite (d) 100% tempered martensite

Propane gas $(C_3H_8)$ at $25^\circ C,$ 1 atm enters a reactor operating at steady state and burns with 20% excess au entering at $25^\circ C,$ 1 atm. Of the carbon entering with the fuel, 94% (molar basis) appears in the products as $CO_2$ and the rest as CO. Heat transfer from the reactor occurs at a rate of $1.4 \times 10^6 kJ$ per kmol of propane. Ignoring kinetic and potential energy effects, determine the temperature of the combustion products exiting the reactor, in K.

Methyl alcohol $(CH_3OH)$ burns with 200% theoretical air, yielding $CO_2, H_2O, O_2,$ and $N_2.$ Determine the a. balanced reaction equation. b. air-fuel ratio on a mass basis. c. molar analysis of the products.

Determine the lower heating value, in kJ per kmol of fuel and in kJ per kg of fuel, at $25^\circ C,$ 1 atm for a. gaseous ethane $(C_2H_6).$ b. liquid ethanol $(C_2H_5OH).$ c. gaseous propane $(C_3H_8).$ d. liquid octane $(C_8H_{18}).$

A sample of dried Appanoose County coal has a mass analysis of 71.1 % carbon, 5.1 % hydrogen $(H_2),$ 9.0% oxygen $(O_2),$ 1.4% nitrogen $(N_2),$ 5.8% sulfur, and the rest noncombustible ash. For complete combustion with the theoretical amount of air, determine a. the amount of $SO_2$ produced, in kg per kg of coal. b. the air-fuel ratio on a mass basis.

Butane $(C_4H_{10})$ burns completely with 160% of theoretical air at $20^\circ C,$ 1 atm, and 90% relative humidity. Determine a. the balanced reaction equation. b. the dew point temperature, in $^\circ C,$ of the products, when cooled at 1 atm.

Verify each identity.

$$\cos 4 t = 8 \cos ^ { 4 } t - 8 \cos ^ { 2 } t + 1$$

Escribe comparaciones con la siguiente información. El caldo cuesta $5 y el gazpacho cuesta$8.

Propane $(C_3H_8)$ at 298 K, 1 atm, enters a combustion chamber operating at steady state with a molar flow rate of 0.7 kmol/s and burns completely with 200% of theoretical air entering at 298 K, 1 atm. Kinetic and potential energy effects are negligible. If the combustion products exit at 560 K, 1 atm, determine the rate of heat transfer for the combustion chamber, in kW. Repeat for an exit temperature of 298 K.

Use a graphing utility to graph the function. Identify any symmetry with respect to the x-axis, y-axis, or origin. Determine the number of x-intercepts of the graph. $g(x)=\frac{1}{5}(x+1)^{2}(x-3)(2 x-9)$

The total sustained load on the concrete footing of a planned building is the sum of the dead load plus the occupancy load. Suppose that the dead load

$$X _ { 1 }$$

has a gamma distribution with

$$\alpha _ { 1 } = 50 \text { and } \beta _ { 1 } = 2$$

, whereas the occupancy load

$$X _ { 2 }$$

has a gamma distribution with

$$\alpha _ { 2 } = 20 \operatorname { and } \beta _ { 2 } = 2$$

. (Units are in kips.) Assume that

$$X _ { 1 } \text { and } X _ { 2 }$$

are independent. Find a value for the sustained load that will be exceeded with probability less than 1/16.