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QJEEM24Chdfb4: JEE Main 2024 Chemistry - Class 11 JEEM24Chdfb4 Solution: Based on Heisenberg's uncertainty principle, the uncertainty in …

Based on Heisenberg's uncertainty principle, the uncertainty in the velocity of the electron to be found within an atomic nucleus of diameter 10−15 m is ________ ×109 ms−1 (nearest integer)

[Given : mass of electron =9.1×10−31 kg, Plank's constant (h)=6.626×10−34Js] (Value of π=3.14)

Step-by-Step Verified Solution

To find the uncertainty in the velocity of the electron within an atomic nucleus of diameter 10−15 m10^{-15} \ \text{m} , we can use Heisenberg's uncertainty principle. The principle is expressed as:

Δx⋅mΔv≥h4π\Delta x \cdot m \Delta v \geq \frac{h}{4 \pi}

Here, Δx\Delta x is the uncertainty in position, mm is the mass of the electron, Δv\Delta v is the uncertainty in velocity, and hh is Planck's constant.

Given:

  • Δx=10−15 m\Delta x = 10^{-15} \ \text{m}

  • m=9.1×10−31 kgm = 9.1 \times 10^{-31} \ \text{kg}

  • h=6.626×10−34 Jsh = 6.626 \times 10^{-34} \ \text{Js}

  • π=3.14\pi = 3.14

We need to find Δv\Delta v . Rearrange the uncertainty principle to solve for Δv\Delta v :

Δv≈h4πmΔx\Delta v \approx \frac{h}{4 \pi m \Delta x}

Plug in the numbers:

Δv=6.626×10−344×3.14×9.1×10−31×10−15\Delta v = \frac{6.626 \times 10^{-34}}{4 \times 3.14 \times 9.1 \times 10^{-31} \times 10^{-15}}

First, calculate the denominator:

4×3.14×9.1×10−31×10−15=114.392×10−464 \times 3.14 \times 9.1 \times 10^{-31} \times 10^{-15} = 114.392 \times 10^{-46}

Now, perform the division:

Δv=6.626×10−34114.392×10−46=6.626114.392×1012\Delta v = \frac{6.626 \times 10^{-34}}{114.392 \times 10^{-46}} = \frac{6.626}{114.392} \times 10^{12}

Perform the division:

Δv≈0.0579×1012 m/s=57.97×109 m/s\Delta v \approx 0.0579 \times 10^{12} \ \text{m/s} = 57.97 \times 10^9 \ \text{m/s}

So, the uncertainty in the velocity of the electron is:

58×109 m/s(nearest integer)58 \times 10^{9} \ \text{m/s} \quad \text{(nearest integer)}

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