Structure of Atom

An atom has 6 protons, 6 electrons, and 6 neutrons. What is its mass number?

Which particle is found outside the nucleus?

Why did Rutherford's model suggest that the atom is unstable?

Which of these is a characteristic of alpha particles?

In a discharge tube, the discovery of 'Canal Rays' (anode rays) revealed that they are not emitted by the anode itself. Based on the provided process diagram, how are these positive rays actually generated?

Which statement best describes a proton?

When cathode rays strike a heavy metal target like Tungsten, they produce:

Which of the following statements about the nucleus is true according to Rutherford's model?

In the discharge tube, the glow observed on the walls behind the perforated cathode is due to:

An atom has 7 protons, 7 neutrons, and 7 electrons. What is its mass number?

Which of these is a correct conclusion of the cathode ray experiment?

The mass of an electron is so small that it is usually ________ in most atomic mass calculations.

J.J. Thomson's work on electrons took place around the year:

The direction of deflection of cathode rays in a magnetic field follows which rule?

In his experiments, J.J. Thomson changed the metal used for the cathode (such as using iron, copper, or platinum) and observed that the deflection and properties of the resulting cathode rays did not change. What fundamental conclusion was drawn from this specific observation?

When the voltage in a discharge tube is increased, the velocity of the cathode ray particles increases. If the velocity of an electron in the beam is doubled, how does its kinetic energy ($KE = \frac{1}{2}mv^2$) change, and what is the consequence when it hits a metal target?

Which of the following represents the correct charge-to-mass ratio calculation setup?

In modern terminology, cathode rays are essentially:

Which of the following scientists is primarily associated with the 'Maltese Cross' experiment to show straight-line travel of cathode rays?

If the distance between the cathode and anode is increased, but the voltage and pressure are held constant, what happens to the discharge?

According to the properties of canal rays, they travel in ________ lines.

Goldstein's discovery proved that the atom has a ___________ part.

What happens to the velocity of canal ray particles if the voltage is increased?

Which subatomic particle is located inside the nucleus along with neutrons?

In a discharge tube experiment, both cathode rays and canal rays are accelerated by the same electric field. Even though both particles can carry the same magnitude of charge (like a proton and an electron), canal rays are observed to travel at a much lower speed. Based on the discovery of subatomic particles, what is the fundamental reason for this difference in speed?

If the pressure in the discharge tube is too high, why are canal rays not observed?

A hydrogen atom loses one electron. The remaining particle is:

The canal rays moving towards the cathode possess:

Which discovery directly led to the conclusion that protons are located in a central nucleus?

Which of the following rays is not affected by electric and magnetic fields?

If an element has atomic number 17 and mass number 35, how many neutrons does it have?

Isotopes of the same element have the same number of protons but different numbers of:

Which subatomic particle was the last to be discovered?

In Chadwick's experiment, the conservation of which two quantities was used to determine the mass of the neutron?

If an atom loses a neutron, what specifically changes?

The discovery of neutrons explained why the atomic mass of Helium is 4, even though its atomic number is:

Which scientist proposed the existence of a neutral particle in the nucleus as early as 1920, before it was discovered?

In the discovery of the neutron, Chadwick used the principle of elastic collision. If a neutron of mass $m$ and velocity $v$ hits a stationary proton of mass approximately $m$, what happens to the velocity of the neutron and proton after a head-on collision?

Which of the following isotopes has the highest neutron-to-proton ratio?

A nucleus has Z protons and N neutrons. Its mass $M$ is found to be slightly less than the sum of the masses of individual protons ($m_p$) and neutrons ($m_n$). This is due to:

Which shell is closest to the nucleus?

The velocity of light ($c$) is approximately:

When an atom emits a photon, the energy of the photon equals:

A continuous spectrum is produced by:

What determines the atomic number of an element?

Which of the following is the correct mass of an electron?

How many electrons are in the outermost shell of an atom of Argon ($Z=18$)?

The splitting of spectral lines in the presence of a magnetic field is known as:

Which of the following is the correct formula for the wave number of the Balmer series lines?

The ratio of the energy of a photon of $2000 \text{ \AA}$ wavelength to that of $4000 \text{ \AA}$ wavelength is:

The line spectrum of hydrogen is also known as:

When an electron returns to the ground state from an excited state, it releases energy in the form of:

Which shell corresponds to the value $n = 4$?

The energy of an orbit in Bohr's model is:

Which electronic transition in the hydrogen atom requires the most energy absorption?

The number of spectral lines produced when an electron returns from $n=n$ to $n=1$ is given by the formula:

If an electron in hydrogen is excited to $n=2$, how much energy (in eV) must it have absorbed from the ground state ($n=1$)?

The Bohr model could not explain the spectrum of which of the following species?

Which of the following values is closest to the radius of the second orbit of a hydrogen atom?

The wavenumber of the $H_\alpha$ line of the Balmer series is $15200 \, cm^{-1}$. What is the wavenumber of the $Li^{2+}$ ion for the same transition?

Rutherford's model was a step forward because it identified the ______.

The limitation of Rutherford's model is based on the behavior of ______.

What provides the centripetal force in Rutherford's model?

The spiraling electron in Rutherford's flawed model would emit a ______ spectrum.

While Rutherford's model provided a revolutionary view of the atomic center, it remained incomplete for chemistry because it could not explain the basis of the periodic table. Based on the diagram, which specific limitation prevents this model from explaining why different elements have different chemical reactivities?

To resolve Rutherford's limitation, Bohr proposed that electrons move in 'special' orbits called ______.

What is the main reason why classical mechanics fails at the atomic level?

Why is the Rutherford model still taught today despite these major 'advanced' limitations?

If Rutherford's model were correct, what would be the relationship between the temperature of a gas and the light it emits?

A student argues that Rutherford's model is correct because electrons are so light they don't radiate much energy. Why is this scientifically incorrect?

According to the Bohr-Bury rule, the outermost shell cannot have more than 8 electrons even if it has the capacity to hold more. Which element first demonstrates the need for a new shell after 8 electrons in the $M$ shell?

Valency of an element with atomic number 13 is:

If $Z$ is the atomic number, for which element is the electronic configuration 2, 8, 8?

Which of these subatomic particles is NOT involved in Bohr's electronic configuration rules?

An atom of an element has 19 protons. According to Bohr's model and the Bohr-Bury rules, if this atom loses its single valence electron to achieve a stable electronic configuration, which shell becomes the new outermost shell and how many electrons will it contain?

In the electronic configuration of Aluminum ($2, 8, 3$), how many electrons are in the $L$ shell?

According to Bohr, as long as an electron revolves in a particular orbit, its energy:

For an electron in the $n^{th}$ orbit of a hydrogen atom, the time period of revolution is proportional to:

If an atom has a total of 11 electrons, how many electrons are in the orbits with $n > 1$?

Which of the following experimental results was Bohr trying to explain with his model of discrete energy levels?

The term 'discrete' in discrete orbits means:

Bohr's model is often called the ____ model of the atom.

According to the $2n^2$ rule, if $n=4$, the number of electrons is:

The idea that electrons revolve in paths called 'orbits' was first popularized by which model?

What is the name given to the path of an electron around the nucleus in Bohr's model?

How many electrons are present in the valence shell of Noble gases (except Helium)?

The achievement of Bohr's model in defining 'Valence Electrons' helped explain:

What is the angular momentum of an electron in the 4th orbit of a Hydrogen atom?

Which transition in the Hydrogen atom emits a photon in the visible range (Balmer series)?

The radius of the orbit is directly proportional to:

Which of the following describes a major 'Advanced' limitation of Bohr's model?

A key limitation of Bohr's model is that it treats an atom like a ________ system, similar to the solar system.

Bohr's model predicts the energy of an electron in an orbit. For Hydrogen, this energy depends only on:

Because Bohr's model treats the electron as a particle only, it cannot explain ______ phenomena.

In conclusion, Bohr's model is limited because it is a ________ description of a ________ system.

Which of these is a 'Hydrogen-like species' that Bohr's model could explain?

The Stark effect and Zeeman effect proved that Bohr's energy levels are ________ than Bohr suggested.

If Bohr's model were correct, what should happen to an electron as it moves in its orbit, according to Maxwell's theory of electromagnetism?

Bohr's model assumed that electrons rotate in a circular path like planets. What is the major physical flaw in this planetary analogy?

Which scientist's principle regarding the limitation of simultaneous measurements of conjugates was most damaging to Bohr's 'fixed orbit' theory?