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A cargo truck blow its horn and can be heard at a distance of 10.0 m with a sound intensity level 93.0 dB. If 6 identical cargo trucks simultaneously blow their horns, what combined sound intensity level can be heard at a distance of 10.0 m form these trucks?
A person wears a hearing aid that uniformly increases the intensity level of all audible frequencies of sound by 30.0 dB. If the hearing aid picks up a sound with an intensity of 3.5 x 10-9 W/m2 , what is the sound intensity delivered to the eardrum?
Use the Lagrange multipliers to solve the following:
Maximize f(x,y,z) = 4x + 2y + z
subject to x2 + y + z2 = 1
The following acids are arranged in order of increasing strength:
HClO< CH3COOH < HNO2 < HI
The correct order of the increasing strength of their conjugate bases is:
A bullet fired at an angle θ = 60degress with a velocity of 30 m/s.
Acceleration due to gravity is 10 m/s2. What is the time interval to
reach the maximum height?
1.1 On which very old object does a table of prime numbers appear?
To get a sense of the effect of cellular conditions on the ability of adenosine triphosphate (ATP) to drive biochemical processes, compare the standard Gibbs energy of hydrolysis of ATP to ADP (adenosine diphosphate) with the reaction Gibbs energy in an environment at 37 °C in which pH = 7.0 and the ATP, ADP, and Pi− concentrations are all 1.0 mmol dm−3.
Consider the cell, Zn(s)|ZnCl2(0.0050 mol kg−1)|Hg2Cl2(s)|Hg(l), for which the cell reaction is Hg2Cl2(s) + Zn(s) → 2 Hg(l) + 2 Cl−(aq) + Zn2+(aq). The cell potential is +1.2272 V, E⦵(Zn2+,Zn) = −0.7628 V, and E⦵(Hg2Cl2,Hg) = +0.2676 V. (a) Write the Nernst equation for the cell. Determine (b) the standard cell potential, (c) ΔrG, ΔrG⦵, and K for the cell reaction, (d) the mean ionic activity and activity coefficient of ZnCl2 from the measured cell potential, and (e) the mean ionic activity coefficient of ZnCl2 from the Debye–Hückel limiting law. (f) Given that (∂Ecell/∂T)p = −4.52 × 10−4 V K−1, Calculate ΔrS and ΔrH.
For a hydrogen/oxygen fuel cell, with an overall four-electron cell reaction 2 H2(g) + O2(g) → 2 H2O(l), the standard cell potential is +1.2335 V at 293 K and +1.2251 V at 303 K. Calculate the standard reaction enthalpy and entropy within this temperature range.
Write the equilibrium constant expression
1. H2(g) + I2(g) ⇌ 2HI(g)
2. 3O2(g) ⇌ 2O3(g)
3. 2CO2(g) ⇌ 2CO(g) +O2(g)
4. CH3COOH (aq) +C2H5OH ⇌ CH3COOC2H5(aq) +H2O(l)
5. AgCl(s) ⇌ Ag+ (aq) Cl (aq)
#339914 on Dec 2023