JEE Main Chemistry: Atomic Structure Practice Questions
11 free multiple-choice questions on Atomic Structure for JEE Main Chemistry, each with the correct answer and a step-by-step explanation. Attempt a question, then reveal the solution to check your reasoning.
Practice thousands more Atomic Structure questions in the app →Q1. The azimuthal quantum number (l) specifies the shape of an orbital. For l=1, which type of orbital is described?
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Correct answer: A — p-orbital
The value of l corresponds to the angular momentum and defines the shape of the orbital: l=0 is s, l=1 is p, l=2 is d, and l=3 is f.
Q2. Which quantum number defines the number of electrons that can occupy a specific energy level (n)?
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Correct answer: B — n
The principal quantum number (n) determines the total number of possible energy states (or orbitals) available within that principal shell.
Q3. How many orbitals are possible for an electron in a given subshell characterized by l=2?
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Correct answer: A — 5
For a given l, the number of magnetic quantum numbers (mₗ) ranges from -l to +l, giving 2l+1 orbitals. If l=2, the number of orbitals is 2(2)+1 = 5.
Q4. If the energy of an electron in a hydrogen atom is increased, how does the physical size of the electron cloud generally change?
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Correct answer: C — Decreases
Higher energy levels correspond to higher principal quantum numbers (n), which means the electron is further from the nucleus, resulting in a larger average orbital size.
Q5. How many distinct spatial orientations (orbitals) are possible for an electron in a subshell where l=3?
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Correct answer: B — 3
The number of orbitals in a subshell is given by 2l+1. For l=3, the number of orbitals is 2(3)+1 = 7.
Q6. For a hydrogen atom, which of the following sets of quantum numbers is NOT possible?
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Correct answer: A — n=1, l=3, m_l=2
The azimuthal quantum number (l) must satisfy 0 ≤ l ≤ n-1. Since n=1, the maximum value for l is 0. Therefore, l=3 is impossible when n=1.
Q7. The azimuthal quantum number (l) for a subshell determines which property of the electron?
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Correct answer: A — Orbital angular momentum
The azimuthal quantum number (l) describes the shape of the orbital and is related to the orbital angular momentum.
Q8. If the principal quantum number n=3, what is the maximum possible value for the azimuthal quantum number l?
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Correct answer: C — 2
For a given n, the possible values for l range from 0 to n-1. Thus, for n=3, the maximum l is 3-1=2.
Q9. For a given value of the azimuthal quantum number l, the number of distinct spatial orientations (orbitals) available is determined by which quantum number?
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Correct answer: B — m_l
The number of distinct spatial orientations (orbitals) for a given l is determined by mₗ, and the number of possible values for mₗ is 2l+1.
Q10. Which principal quantum number (n) dictates the maximum number of electrons that can be accommodated in a specific energy level shell?
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Correct answer: B — n=1
The principal quantum number (n) defines the main energy level and determines the maximum number of electrons (2n) that can occupy that shell.
Q11. The azimuthal quantum number (l) determines the shape of the orbital. For the principal quantum number n=3, what are the possible values for l?
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Correct answer: C — 0, 1, 2
For a given n, the possible values for l are 0, 1, 2, ..., n-1. Thus, for n=3, the possible values for l are 0, 1, and 2.
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