Chemistry Ch 2 Heisenberg

Question 1

Ap= uncertainty in momentum of particle

Question 2

AVX = uncertainty in velocity of particle

Question 3

Explanation : If the position of electron is

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known (Ar is small)

Answer 4

then the velocity of the

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electron will be uncertain in large.

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IE the velocity of the electron is known

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precisely

Answer 7

then the position of the electron will

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be uncertain. Thus

Answer 8

if we carry out some

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physical measurements of the electron’s

Question 10

position or velocity

Answer 10

the outcome will always

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depict a fuzzy or blur pictúre.

Question 12

To decide position of electron : In order to

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determine the position of an electron

Answer 13

we must-

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use a meterstick calibrated in units of smaller

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than the dimensions of electron.

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To observe an electron

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we can illuminate it

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with “light” or electromagnetic radiation. The

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“light” used must have a wavelength smaller

Question 19

than the dimensions of an electron.

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The high momentum photons of such light

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would change the energy of electrons

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by collisions. In this process we

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no doubt

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would be able to calculate the position of the

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electron

Answer 24

but we would know very little about

Question 25

the velocity of the electron after the collision.

Question 26

Significance of uncertainty principle : One of

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the important implications of the Heisenberg

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Uncertainty Principle is that it rules out

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existence of definite paths or trajectories of

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electrons and other similar particles.

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The trajectory of an object is determined by

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its location and velocity at various moments. If

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we know where a body is at a particular instant

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and if we also know its velocity and the forces

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acting on it at that instant

Answer 35

we can tell where

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the body would be sometime later.

Question 37

Since for a sub-atomic object such as an

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electron

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it is not possible simultaneously to

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determine the position and velocity at any given

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Instant to an arbitrary degree of precision

Answer 40

it is

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not possible to talk of the trajectory of an

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electron.

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Limitation: The effect of Heisenberg Uncertainty

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Principle is significant only for motion of

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microscopic objects and is negligible for that of

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macroscopic objects.

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# UID : P1-C2-S1-Q52

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