C, Land heats and cools faster than water!
The boiling point of ethanol is at 78.37°C. So, the energy must include sensible heat to raise 19°C to the boiling point and latent heat to change liquid to gas. The equation would be
Energy = Sensible heat + Latent heat
Energy = mCpΔT + mΔH
For ethanol,
Cp = 46.068 + 102,460T - 139.63T² - 0.030341T³ + 0.0020386T⁴ J/kmol·K
ΔH = 38,560 J/mol
Integrate the Cp expression to determine CpΔT:
CpΔT = ∫₂₉₂³⁵²(46.068 + 102,460T - 139.63T² - 0.030341T³ + 0.0020386T⁴ )dT
The upper limit is (78.37+273) = 352 K, while the lower limit is (19 + 273) = 292.
CpΔT = 2384857192 J/kmol·K
2,000 J = m(2384857192 J/kmol)(1 kmol/1000 mol) + m(38,560 J/mol)
m = 8.253×10⁻⁴ moles of ethanol
Since the molar mass of ethanol is 46.07 g/mol,
Mass = (8.253×10⁻⁴ mol)(46.07 g/mol)
Mass = 0.038 g ethanol
Answer:
The angle is 18.3 degree.
Explanation:
A uniformly charged infinite plane, density σ = 4 x 10^-9 C/cm^2, is placed vertically in air. A small ball of mass 8 g, with charge q = 10^-8 C, hangs close to the plane, so that the string is initially parallel to the plane. Take g = 9.8m/s2. When in equilibrium, by what angle is the string hanging the ball to the plane?
surface charge density, σ = 4 x 10^-5 C/m^2
Charge, q = 10^-8 C
mass, m = 0.008 kg
Let the angle is A and the tension in the string is T.
The electric field due to a plane is
Now equate the forces,
The answer is CFC – 22 or HCFC - 22. To locate leaks, it is
easily accomplished using a pressure – regulated dry nitrogen charge with CFC –
22. But some technicians prefer to use Refrigerant – 22 (HCFC – 22) to
pressurize the system without the use of nitrogen. CFC – 22 is also known as Chlorodifluoromethane.
This is a hydrochlorofluorocarbon (HCFC). This is better recognized as HCFC-22, or R-22. It is usually
used as a propellant and refrigerant. While HCFC
– 22 is also known as class II hydrochlorofluorocarbon refrigerant that is less
harmful to the ozone than R -12. If HCFC – 22 is used for leak testing, all
refrigerant must be first detached from the system. After the leak test, HCFC –
22 should be remove before putting any other refrigerant. Do not mix refrigerants.
Both HCFC – 22 and R -134a fall into the kind of refrigerants known as
combustible. If exposed to oxygen, they will burn when under pressure or
exposed to high temperatures.
Answer
The colder areas of its body are darker in color (extremities)
Explanation:
Siamese cats fur is darker in the cooler parts of the skin (extremities), such as ears, nose, tail and paws. Conversely, warmer parts of the body were associated with white- or light grey-colored fur. Moreover, Siamese cats have a highly recognized 'mask' on their face for the same reason.
Hope this help If it did plz mark brainliest
Have a nice day!!
