(A) The number of moles $n$ is given by the formula $n = \frac{\text{mass}}{\text{molar mass}}$.Given mass $= 39.4$ $g$ and molar mass $= 197$ $g$ $mo

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(A) The number of moles $n$ is given by the formula $n = \frac{\text{mass}}{\text{molar mass}}$.Given mass $= 39.4$ $g$ and molar mass $= 197$ $g$ $mol^{-1}$.$n = \frac{39.4}{197} = 0.2$ $mol$.The number of atoms $N$ is calculated by multiplying the number of moles by Avogadro's number $N_A = 6.023 \times 10^{23}$ $mol^{-1}$.$N = n \times N_A = 0.2 \times 6.023 \times 10^{23} = 1.2046 \times 10^{23}$ atoms.

Class 12 Physics Atoms Atomic Models and Scattering of Alpha particle

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Calculate the number of atoms in $39.4$ $g$ of gold. The molar mass of gold is $197$ $g$ $mol^{-1}$.

A
$1.2046 \times 10^{23}$
B
$2.4092 \times 10^{23}$
C
$0.6023 \times 10^{23}$
D
$3.0115 \times 10^{23}$

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Atoms

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Atomic Models and Scattering of Alpha particle

State the atomic hypothesis regarding the structure of matter.

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In the Geiger-Marsden experiment,which of the following is used to calculate the trajectory of the $\alpha$-particle?

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We consider the Thomson model of the hydrogen atom in which the proton charge is distributed uniformly over a spherical volume of radius $R = 0.25 \,\mathring A$. Applying the Bohr quantization condition in this model,the ground state energy (in $eV$) of the electron will be close to:

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The diagram shows the path of four $\alpha$-particles of the same energy being scattered by the nucleus of an atom. Which of these is/are not physically possible?

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Which statement about the Rutherford model of the atom is not true?

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Calculate the number of atoms in $39.4$ $g$ of gold. The molar mass of gold is $197$ $g$ $mol^{-1}$.

Similar Questions

State the atomic hypothesis regarding the structure of matter.

In the Geiger-Marsden experiment,which of the following is used to calculate the trajectory of the $\alpha$-particle?

We consider the Thomson model of the hydrogen atom in which the proton charge is distributed uniformly over a spherical volume of radius $R = 0.25 \,\mathring A$. Applying the Bohr quantization condition in this model,the ground state energy (in $eV$) of the electron will be close to:

The diagram shows the path of four $\alpha$-particles of the same energy being scattered by the nucleus of an atom. Which of these is/are not physically possible?

Which statement about the Rutherford model of the atom is not true?

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