Atom Calculator
Calculate atomic properties: protons, neutrons, electrons, mass number, and charge
Calculate Atomic Properties
Positively charged particles
Neutral particles in nucleus
Negatively charged particles
Atomic Composition Results
Calculation Method
Calculation Steps
Atomic Structure Analysis
Key Equations
Example: Sodium Atom Calculation
Given Information
Element: Sodium (Na)
Atomic number (Z): 11
Mass number (A): 23
Charge (z): 0 (neutral atom)
Step-by-Step Calculation
1. Number of protons = Atomic number = 11
2. Number of neutrons = Mass number - Atomic number = 23 - 11 = 12
3. Number of electrons = Atomic number - Charge = 11 - 0 = 11
Result: Sodium atom has 11 protons, 12 neutrons, and 11 electrons
Subatomic Particles
Ion Classification
Quick Reference
Z = atomic number = protons
A = mass number = p⁺ + n⁰
Charge = p⁺ - e⁻
Isotopes have same Z, different A
Atomic mass ≈ mass number
Understanding Atomic Structure
What is an Atom?
An atom is the smallest constituent unit of matter that retains the properties of an element. It consists of a dense nucleus containing protons and neutrons, surrounded by electrons in orbital shells. The arrangement and number of these particles determine the element's identity and chemical properties.
Key Components:
- • Nucleus: Dense core containing protons and neutrons
- • Electron Cloud: Probability regions where electrons are found
- • Atomic Number (Z): Number of protons (element identity)
- • Mass Number (A): Total nucleons (protons + neutrons)
Atomic Calculations
From Components
Given p⁺, n⁰, e⁻ → Calculate Z, A, charge
From Properties
Given Z, A, charge → Calculate p⁺, n⁰, e⁻
Element Lookup
Standard values for common elements
Applications in Chemistry
Element Identification
Atomic number uniquely identifies each element on the periodic table.
Isotope Analysis
Different neutron numbers create isotopes with varying nuclear properties.
Ion Formation
Electron gain/loss creates charged ions important in chemical bonding.
Important Relationships
Fundamental Equations
Atomic Number: Z = p (defines element)
Mass Number: A = p + n (nucleon count)
Net Charge: z = p - e (electrical balance)
Neutrons: n = A - Z (nuclear composition)
Special Cases
Neutral Atom: p = e (no net charge)
Cation: p > e (positive charge)
Anion: p < e (negative charge)
Isotopes: Same Z, different A