The question is incomplete. Here is the complete question.
An atom of lead has a radius of 154 pm and the average orbitalspeed of the electron in it is about 1.8x
m/s. Calculate the least possible uncertainty in a measurement of the speed of an electron in an atom of lead. Write your answer as a percentage of the average speed, and round it to significant 2 digits.
Answer: v% = 0.21 m/s
Explanation: To calculate the uncertainty, use <u>Heisenberg's Uncertainty Principle</u>, which states that: ΔpΔx≥
where h is <u>Planck's constant</u> and it is equal to 6.626.
m²kg/s.
Since p (momentum) is p = m.v:
mΔv.Δx ≥
Δv = 
Given that: r = x = 1.54.
m and mass of an electron is m=9.1.
kg
Δv = 
Δv = 0.0376.
As percentage of average speed:
Δv.
.100% = 
.10² = 0.021.10 = 0.21%
The least possible uncertainty in a speed of an electron is 0.21%.
Answer:
27.99 dm³
Explanation:
Applying
PV = nRT................ Equation 1
Where P = Pressure, V = Volume, n = number of mole, R = molar gas constant, T = Temperature.
From the question, we were aksed to find V.
Therefore we make V the subject of the equation
V = nRT/P................ Equation 2
Given: n = 1.31 moles, T = 37°C = 310K, P = 904 mmHg = (904×0.001316) = 1.1897 atm
Constant: R = 0.082 atm.dm³/K.mol
Substitute these values into equation 2
V = (1.31×310×0.082)/(1.1897)
V = 27.99 dm³
The wall would absorb extra heat during the day when the sun is out, then release the heat back into the room when the sun goes down.
Answer:
234.68g
Explanation:
We understood from Avogadro's hypothesis that 1mole of any substance contains 6.02x10^23 atoms. Therefore, 1mole of Fe2O3 also contains 6.02x10^23 atoms
1 mole of Fe2O3 = (56x2) + (16x3) = 112 + 48 = 160g
Now, if 160g of Fe2O3 contains 6.02x10^23 atoms,
Therefore Xg of Fe2O3 will contain 8.83×10^23 atoms i.e
Xg of Fe2O3 = (160x8.83×10^23)/6.02x10^23 = 234.68g
