Answer:
114 kPa
Explanation:
By Bernoulli's equation when a fluid flows steadily through a pipe:
P + ρ*g*y + v² = constant in the pipe, where P is the pressure, ρ is the density of the fluid, g is the gravity acceleration (9.8 m/s²), y is the high, and v the velocity.
By the continuity equation, the liquid flow must be constant in the pipe, and then:
A1*v1 = A2*v2
Where A is the area, v is the velocity, 1 is the point 1, and 2 the point 2 in the pipe. The are is the circle area: π*(d/2)². So:
π*(0.105/2)²*9.91 = π*(0.167/2)²*v2
0.007v2 = 0.027
v2 = 3.9 m/s
Then:
P1 + ρ*g*y1 + v1² = P2 + ρ*g*y2 + v2²
ρ*g*y1 - ρ*g*y2 + v1² - v2² = P2 - P1
ρ*g*Δy + v1² - v2² = ΔP
ΔP = 1290*9.8*9.01 + 9.91² - 3.9²
ΔP = 113,987.42 Pa
ΔP = 114 kPa
Answer:
c. Only certain energies are allowed for the electron in a hydrogen atom
Explanation:
Emission spectrum are produced when the excited electron in a atom release the energy in the form of photons to come to ground state. These photons are of different wavelengths depending on the excitation state of emitting electron or transition of electron. These electromagnetic radiation are observed through prism to produce the spectrum.
As the name indicates this spectrum is produced by emission of energy. Although the electron can be excited by different methods such as by heating but the key point is that electrons in hydrogen atom will emit the photons of same energy which they absorb and each electron can absorb only certain type of energy. So four lines were observed in the visible spectrum of hydrogen because only certain energies are observed for hydrogen atom.
Answer:
Molar mass = 0.09 × 10⁴ g/mol
Explanation:
Given data:
Mass = 0.582 g
Volume = 21.3 mL
Temperature = 100°C
Pressure = 754 mmHg
Molar mass = ?
Solution:
(21.3 /1000 = 0.0213 L)
(100+273= 373 K)
(754/760 = 0.99 atm)
PV = nRT
n = PV/RT
n = 0.99 atm × 0.0213 L / 0.0821 atm. L. mol⁻¹. k⁻¹ × 373 K
n =0.02 mol/ 30.6
n = 6.5 × 10⁻⁴ mol
Molar mass = Mass/ number of moles
Molar mass = 0.582 g / 6.5 × 10⁻⁴ mol
Molar mass = 0.09 × 10⁴ g/mol
Answer:
2.05 × 10²³ formula units
Explanation:
Given data:
Mass of AgF = 43.15 g
Number of formula units = ?
Solution:
Number of moles of AgF:
Number of moles = mass/ molar mass
Number of moles = 43.15 g/ 126.87 g/mol
Number of moles = 0.34 mol
Now Number of formula units will be determine by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number
1 mole = 6.022 × 10²³ formula units
0.34 mol × 6.022 × 10²³ formula units
2.05 × 10²³ formula units
Answer: Number of atoms in 
of radon gas (radon atoms) at the same temperature and pressure is 
Explanation:
According to avogadro's law, volume of a gas is directly proportional to the number of moles present when temperature and pressure is constant.:
= moles of hydrogen gas = 
= moles of radon gas = ?
Thus the number of atoms in of radon gas (radon atoms) at the same temperature and pressure is
