11) 2NH3(g)+3O2(g)+2CH4(g) --->2HCN(g) +6H2O(g)

^=-45.9 kj ^=-74.87kj ^= 135.1kj ^= -241.8kj

a) Calculate delta H rxn

b) Calc q when 25.0 g CH4 reacts

c) If 10.0L of each reactant was used at STP what V of HCN would be formed?

d) If 6.0L of HCN was formed? calc % yield

A body of mass 7 kg is projected vertically upward with an initial velocity 18 meters per second. The gravitational constant is g=98m/s². The air resistance is equal to k|v| where k is a constant.

Find a formula for the velocity at any time ( in terms of k ):

Find the limit of this velocity for a fixed time t₀ as the air resistance coefficient k goes to 0.

A Nd: YAG Laser with a length of 0.01m is coated on both sides so that R=0.95

wavelength= 1.0?m

the linewidth of the laser transition is v = 10/cm

Absorption coefficient a=0.01/cm

Lifetime of upper laser level l = 3ms

refractive index n = 1.77

A. What is the minimum invertsion population requirement for lasing?

B. What is the Q of the Cavity?

A Diesel engine with a compression ratio of 16 has a cutoff ratio of 1.5. The state before polytropic compression (exponent 1.3) is 1700 cm3, 96 kPa and 22°C and there is isentropic expansion.
(a) Sketch the P-v diagram for this cycle.

(b) Calculate the heat transfer in and heat transfer out.

(c) Determine the thermal efficiency.

(d) Calculate the mean effective pressure.

A car and the suspension system are a damped spring, mass system, with a natural frequency 2 Hz and a damping coefficient 0.2. The car drives at speed V over a road with sinusoidal roughness. The roughness wavelength is 20 m, with a amplitude of 50 cm. What speed does the maximum amplitude of vibration occur? What is the corresponding vibration amplitude?

Please do not use an older solution.

for low pressure effusion of gases

how do I calculate area of pinhole and pinhole diameter?

ln(P/P₀) = -Ct

dP/P = - (A/V)(RT/2πM)^1/2 dt = -C dt

(volume= 285cm³, T= 298.15K)

I got relaxation constant  0.01049 microns/second = C

This is for N2 ( nitrogen)

How do i solve A (pinhole are)?

2.50 mole of perfect gas at 0°C is expanded from an initial pressure of 5.00 atm to a final pressure of 1.00 atm against a constant external pressure of 1.00 atm. (a) isothermally and (b) adiabatically. (1) Calculate the values of q, w, DU, DH, DS, DSsur and DStot for (a) and (b) (2) Draw p -V diagram to represent these two different paths.

For cell Al I Al3+ 1M II Be2+ 1x10^-4 M I Be (s) Write the overall net ionic equation Calculate the cell potential E cell at 25 C and predict the spontaneity of the overall reaction Calculate the cell potential at 300 degrees C and predict the spontaneity of the overall reaction The standard reduction potentials are Al- -1.66V Be -1.85 V

0.737 g of a sample contains iron. all amount of iron is oxidied to Fe2+ on Pt anode which has constant potential at 1.0 V against SCE. an iodide chemical coulometer is used to measure the amont of current (Q), the amount of released iodide needs 27.mL of thiosulfate (0.0217 N). calculate the percentage of Fe3O4 in the sample. (current 10 mA)

A particular laser pointer emits a beam with an average power of 5.00 mW, and the beam has a circular cross-section with a diameter of 3.00 mm. The beam is linearly polarized. The average intensity of the light is 707.7 W/m². Determine the following.

(a) the amplitude of the oscillating electric field in the laser beam (V/m)

(b) the amplitude of the oscillating magnetic field in the laser beam (T)