Achieve #19

[Nova Akhavan 2F]

For the following problems: "What is the minimum uncertainty in an electron's velocity (Δvmin) if the position is known within 15 Å."

"What is the minimum uncertainty in a helium atom's velocity (Δvmin) if the position is known within 1.0 Å."

What equation should I use to solve these? I'm not sure how I'm supposed to tackle them.

[cecilia1F]

Hello,
These problems require you to think about the heisenberg's uncertainty equation which tells us that the uncertainty in position times the uncertainty in momentum must be less than or equal to planks constant divided by 4pi.

[Jaylin Hsu 1C]

Hi, just like the post above mentioned, the Heisenberg Uncertainty Principle should be used. We have all the unknown values except the uncertainty in velocity. It is important to remember that the mass of an electron is 9.11*10^-31 kg.

[loganchun]

Hi, for both problems, you are using Heisenberg's uncertainty equation solving for deltav. For the first equation, you would use planck's constant, the mass of an electron, and the uncertainty in position that you found from converting Angstrom's into m. For the second equation you would do the same thing except for when finding the mass of He. To find mass of He, you would use the molar mass of He dividing it by Avogadro's number and converting it from g to kg. Hope this helps.

[805757847]

Hi,

Heisenberg indeterminacy(uncertainty) principle could be used to solve this problem:
(delta x)*(delta p) >= h/(4pai)
in which delta x describes the uncertainty of position, in other words, the range of position
delta p describes the uncertainty of momentum. p = mv, so delta p = m* delta v

Hope this could help!