Atomic Structure Puzzle

Structure of Atom - Drag & Drop Matching

Score: 0 Time: 60s

Electron

Proton

Neutron

Atomic Number

Mass Number

Isotope

Isobar

Bohr Model

Orbital Shape

Quantum Numbers

Negative charge particle

Positive charge particle

Neutral particle

Number of protons

Protons + Neutrons

Same Z, different A

Same A, different Z

Electrons in shells

s, p, d, f

n, l, m, s

📘 Structure of Atom – Quick Definitions

• Electron: A negatively charged particle orbiting the nucleus in specific energy levels.
• Proton: A positively charged particle found inside the nucleus; defines the atomic number.
• Neutron: A neutral particle in the nucleus that adds mass but no charge.
• Atomic Number (Z): Number of protons in the nucleus; determines the element.
• Mass Number (A): Total number of protons and neutrons in an atom.
• Isotopes: Atoms of the same element with different numbers of neutrons.
• Bohr’s Model: Electrons revolve in fixed orbits with quantized energy.
• Quantum Numbers: Numbers that describe the position and energy of an electron.

📘 Quick Definitions — Structure of Atom

Review the key terms used in the game. Tap/click to expand.

Electron

A negatively charged subatomic particle (charge = −1e) that occupies orbitals around the nucleus. Mass ≈ 1/1836 of a proton.

Proton

A positively charged particle (charge = +1e) found in the nucleus. Its count defines the atomic number (Z).

Neutron

An electrically neutral particle in the nucleus. Together with protons it contributes to the atom’s mass number.

Atomic Number (Z)

Number of protons in the nucleus. It uniquely identifies an element (e.g., Z=6 → Carbon).

Mass Number (A)

Total number of nucleons: A = Z + N (protons + neutrons). Determines the isotope of an element.

Isotope

Atoms of the same element (same Z) with different mass numbers (different neutrons). Example: ¹²C and ¹⁴C.

Isobar

Different elements with the same mass number (A) but different atomic numbers (Z). Example: ⁴⁰Ar and ⁴⁰Ca.

Bohr Model

Electrons move in discrete energy shells (n = 1,2,3…). Energy is quantized; electrons jump between shells by absorbing/emitting quanta.

Orbital Shapes (s, p, d, f)

Probability regions for electrons: s (spherical), p (dumbbell), d (clover-like), f (complex). Shape depends on the quantum number ℓ.

Quantum Numbers (n, ℓ, m_ℓ, m_s)

• n: Principal (shell, size/energy)
• ℓ: Azimuthal (subshell/orbital shape)
• m_ℓ: Magnetic (orbital orientation)
• m_s: Spin (+½ or −½)

Valence Electrons & Shell

Electrons in the outermost shell; they control chemical bonding and reactivity (octet/duet rules).

Pauli Exclusion & Hund’s Rule

Pauli: No two electrons in an atom have the same four quantum numbers.
Hund: Electrons occupy degenerate orbitals singly with parallel spins before pairing.

Aufbau Principle

Electrons fill lower-energy orbitals first (approx. order: 1s → 2s → 2p → 3s → 3p → 4s → 3d → …).