Answer:
η = 0.5686
Explanation:
Isentropic compressor efficiency (η):
* η = Isentropic compressor work / real compressor work = Ws / Wreal
∴ Wreal = 76 KW = 76 KJ/s
first law:
∴ Q = 0 ....adiabatic compressor
∴ ΔU = CvΔT
∴ W = - PδV
⇒ ΔU = W ,,,,,isentropic process adiabatic
⇒ CvΔT = - PδV
ideal gas:
⇒ (R + Cv / R) Ln(T2/T1) = Ln (P2/P1)
∴ Cv = 3/2 R....monoatomic ideal gas
∴ R = 8.314 E-3 KJ/K.mol
∴ P1 = 90 KPa
∴ P2 = 800 KPa
∴ T1 = 25 °C ≅ 298 K
∴ r He = 2 Kg/min
⇒ (5/2) Ln(T2/T1) = Ln(800/90) = 2.185
⇒ Ln (T2/T1) = 0.874
⇒ T2/T1 = e∧0.874 = 2.3963
⇒ T2 = (2.3963)(298 K) = 714.094 K
⇒ Ws = CvΔT = (3/2 R)(714.094 - 298 ) = 5.1891 KJ/mol
∴ Mw He = 4.0026 g/mol
⇒ Ws = ( 5.1891 KJ/mol)(mol / 4.0026 g)(1000 g/Kg)(2Kg/min)(min/60s)
⇒ Ws = 43.2144 KJ/s
⇒ η = 43.2144 KJ/s / 76 KJ/s = 0.5686
Answer:
The correct Option is C (It is polar, because the bond polarities add together in a bent molecule.)
Explanation:
The molecular structure of Hydrogen Sulfide (H₂S) is attached below;
The molecule of Hydrogen Sulfide is polar due to following two reasons;
1) Electronegativity Difference:
Sulfur has an electronegativity of 2.58 while that of Hydrogen is 2.20. Hence, sulfur being more electronegative attracts the electron fro hydrogen making it slightly partial positive and increasing electron density and becoming slightly partially positive. So, we can call this bond as slightly polar bond.
2) Dipole Moment:
Dipole moment occurs when the bond is polar. Being a vector quantity it strongly depends upon the geometry of a molecule. In H₂S the two polar bonds cannot cancel each other because they are not in opposite direction as that found in case of CO₂. Hence, H₂S is a polar compound.
Making lemonade is a chemical change because once the ingredients are mixed together they cannot be seperated.
<u>Answer:</u> The wavelength of an electron is
<u>Explanation:</u>
To calculate the wavelength of a particle, we use the equation given by De-Broglie's wavelength, which is:
where,
= De-Broglie's wavelength = ?
h = Planck's constant =
m = mass of electron =
v = velocity of electron =
Putting values in above equation, we get:
Hence, the wavelength of an electron is