G12 ADVANCED MOCK TEST 3

Physics — End of Term Mock Test 3

Obj 11–15  ·  25 Questions  ·  45 Minutes  ·  1 mark each

45:00
TIME REMAINING
0 / 25 answered
Q1Obj 14

If the electron moves from the n=1 orbit to the n=3 orbit in a Hydrogen atom, how does the radius of its orbit change?

AIt triples
BIt increases by a factor of 9
CIt remains the same
DIt decreases by a factor of 3
Q2Obj 12

An electron in a hydrogen atom transitions from the n = 3 energy level to the n = 2 level. Which of the following correctly describes the photon involved in this transition?

AA photon is emitted with energy equal to E3 - E2
BA photon is absorbed with energy equal to E3 - E2
CA photon is emitted with energy equal to E2 - E3
DA photon is absorbed with energy equal to E2 - E3
Q3Obj 15

Which of the following correctly matches the spectral series with its final energy level in the hydrogen atom?

ALyman: n=2, Balmer: n=3, Paschen: n=4
BLyman: n=1, Balmer: n=2, Paschen: n=3
CLyman: n=3, Balmer: n=2, Paschen: n=1
DLyman: n=4, Balmer: n=3, Paschen: n=2
Q4Obj 11

How does the absorption spectrum differ from the emission spectrum of an element?

AThe absorption spectrum shows wavelengths absorbed; emission shows wavelengths emitted
BBoth spectra are identical
CThe absorption spectrum shows emitted light; emission shows absorbed light
DThe absorption spectrum contains only ultraviolet light
Q5Obj 14

Describe how the total energy of the hydrogen atom changes when the principal quantum number increases from n=1 to n=4.

AEnergy becomes four times more negative
BEnergy becomes sixteen times less negative
CEnergy becomes four times less negative
DEnergy remains the same
Q6Obj 13

Why does the Rutherford planetary model fail to explain the stability of atoms?

AElectrons would gain energy and move away from the nucleus
BElectrons would continuously radiate energy and spiral into the nucleus
CThe nucleus would collapse due to electrostatic forces
DElectrons would repel each other and destabilize the atom
Q7Obj 13

Using classical electromagnetism, estimate the time it would take for an electron in a Rutherford atom to spiral into the nucleus if it starts at the Bohr radius (5.3 × 10⁻¹¹ m). Given: electron charge e = 1.6 × 10⁻¹⁹ C, electron mass m = 9.11 × 10⁻³¹ kg, vacuum permittivity ε₀ = 8.85 × 10⁻¹² F/m, and speed of light c = 3.0 × 10⁸ m/s.

AApproximately 10⁻¹¹ s
BApproximately 1 s
CApproximately 10⁻³ s
DIt would never spiral in
Q8Obj 11

An element absorbs light at wavelengths of 500 nm and 600 nm. Calculate the ratio of energies absorbed at these wavelengths.

A1.2
B0.83
C1.5
D0.67
Q9Obj 13

What is the key feature of Rutherford's nuclear model of the atom?

AElectrons are embedded in a positively charged sphere.
BThe atom is a small dense positively charged nucleus surrounded by orbiting electrons.
CElectrons move randomly around the nucleus without fixed paths.
DThe atom consists of electrons and protons evenly distributed throughout.
Q10Obj 11

An absorption line in the spectrum of hydrogen is observed at a wavelength of 410 nm. Calculate the energy of the photon absorbed by the hydrogen atom. (Planck constant h = 6.63 × 10⁻³⁴ J·s, speed of light c = 3.00 × 10⁸ m/s)

A4.85 × 10⁻¹⁹ J
B3.05 × 10⁻¹⁹ J
C6.63 × 10⁻¹⁹ J
D1.52 × 10⁻¹⁹ J
Q11Obj 13

What key feature did Rutherford’s nuclear model introduce that was absent in earlier atomic models?

AElectrons have quantized energy levels
BThe atom contains a central, positively charged nucleus
CAtoms are indivisible and solid spheres
DThe electron’s mass is negligible
Q12Obj 12

Which statement best describes the absorption of a photon by an atom?

AThe atom emits a photon with energy equal to the difference between two energy levels.
BThe atom's electron moves to a lower energy state by absorbing a photon.
CThe atom's electron moves to a higher energy state by absorbing a photon.
DThe atom's nuclear energy levels change after photon absorption.
Q13Obj 14

In the Bohr model of the hydrogen atom, the radius of the electron's orbit for the principal quantum number n is given by r_n = r_1 n^2, where r_1 is the radius of the ground state orbit. If r_1 = 0.053 nm, what is the radius of the orbit when n = 3?

A0.159 nm
B0.477 nm
C0.477 pm
D0.0187 nm
Q14Obj 14

What is the total energy of an electron in the ground state (n=1) of a Hydrogen atom?

A0 eV
B-13.6 eV
C-3.4 eV
D-1.51 eV
Q15Obj 12

Which of the following correctly relates the energy of the emitted photon to the initial and final energy levels of an electron transitioning within an atom?

AE_photon = Ef - Ei
BE_photon = |Ei - Ef|
CE_photon = Ei + Ef
DE_photon = Ei × Ef
Q16Obj 14

What is the relationship between the radius of the electron's orbit in a Hydrogen atom and the principal quantum number n?

AThe radius is proportional to n
BThe radius is proportional to n^2
CThe radius is inversely proportional to n
DThe radius is inversely proportional to n^2
Q17Obj 12

What happens when an atom absorbs a photon with energy equal to the difference between two energy states, Ei and Ef?

AThe atom transitions from energy state Ef to Ei
BThe atom transitions from energy state Ei to Ef
CThe atom emits a photon and remains at energy state Ei
DThe atom remains at energy state Ef without any change
Q18Obj 11

Which of the following best explains why the absorption spectrum of an element is unique?

AEach element has a unique set of electron energy levels
BElements emit light at all wavelengths equally
CAbsorption spectra depend only on the temperature of the element
DAll elements absorb the same wavelengths of light
Q19Obj 15

Which series corresponds to electron transitions that emit photons in the ultraviolet range for hydrogen?

APaschen
BLyman
CBalmer
DBrackett
Q20Obj 12

The energy of a photon emitted or absorbed during an atomic transition is equal to:

AThe sum of the initial and final energy states
BThe difference between the initial and final energy states
CTwice the energy of the initial state
DHalf the energy of the final state
Q21Obj 15

Which series corresponds to electron transitions ending at the n=1 energy level in a hydrogen atom?

ALyman series
BBalmer series
CPaschen series
DBrackett series
Q22Obj 15

What region of the electromagnetic spectrum does the Paschen series primarily emit in?

AUltraviolet
BVisible
CInfrared
DX-ray
Q23Obj 14

If the electron in a hydrogen atom moves from n=5 to n=2, what is the ratio of the orbital radii before and after the transition?

A25:4
B5:2
C4:25
D2:5
Q24Obj 11

Which statement correctly describes the relationship between an element’s absorption spectrum and its identification?

AAbsorption spectra are identical for all isotopes of an element
BThe absorption spectrum acts as a fingerprint allowing element identification
CAbsorption spectra change randomly with time
DAbsorption spectra depend only on the physical state of the element
Q25Obj 15

Calculate the energy difference (in eV) between the n=4 and n=3 levels in hydrogen. (Use E_n = -13.6 eV / n²)

A0.85 eV
B1.89 eV
C0.66 eV
D2.55 eV