Writing a nucleus: ᴬ_Z Xनाभिक लिखने का तरीका: ᴬ_Z XWriting a nucleus: ᴬ_Z X
NCERT Section 13.2 · Class 12 Physics · Chapter 13 · interactive diagram
Read Chapter 13 with this diagramइस डायग्राम के साथ अध्याय 13 पढ़ेंIs diagram ke saath Ch 13 padhiyeAll Physics diagramsसभी भौतिकी डायग्रामSaare Physics diagrams
Parts and what they mean
- Mass number A (द्रव्यमान संख्या A) — Total number of nucleons (protons + neutrons). Written at the top left.
- Atomic number Z (परमाणु क्रमांक Z) — Number of protons = number of electrons in the neutral atom. Nuclear charge = +Ze. Written at the bottom left.
- Chemical symbol X (रासायनिक प्रतीक X) — Au = gold. The symbol already fixes Z, but Z is written for convenience.
- Neutron number N (न्यूट्रॉन संख्या N) — N = A − Z. Gold-197 has 118 neutrons.
- Nucleus (नाभिक) — Protons and neutrons (together called nucleons) packed in a tiny sphere. Electrons are all outside the nucleus.
- Proton (प्रोटॉन) — Charge +e, mass 1.00727 u = 1.67262 × 10⁻²⁷ kg. Stable.
- Neutron (न्यूट्रॉन) — No charge, mass 1.00866 u = 1.6749 × 10⁻²⁷ kg. A free neutron decays (mean life about 1000 s); inside a nucleus it is stable.
Original diagram drawn by Simple Learning Hub, based on NCERT Section 13.2. Report a mistake