Sodium-23, Na⁺
n = 23 − 11 = 12
e = 11 − (+1) = 10
e = 11 − (+1) = 10
The ion loses one electron while retaining 11 protons, so it remains sodium.
Atomic structure dashboard
Periodic Table & Chemistry Calculator
Select one element to calculate its protons, neutrons, electrons, isotope notation, ion structure, electron shells, and exact position in the periodic table.
Element analysis
11Na22.990 u
Sodium
Period 3 · Group 1 · s-block · alkali metal · solid
²³₁₁Na⁺Shells 2, 8Selected ion +1
Click the nucleus, a shell, or an electron to inspect it.
Protons11Defines sodium
Neutrons12Mass 23 − atomic no. 11
Electrons1011 − (+1 charge)
Isotope and ion notation
²³₁₁Na⁺
Electron configuration
[Ne] 3s¹ → simplified ion shells 2, 8
What changes next?
Educational what-if checksIf charge returns to 011 electronsThe atom becomes neutral.
Selected conditionNa-23, +112 neutrons · 10 electrons
If mass number rises by 113 neutronsThe element remains sodium.
Changing electrons creates an ion. Changing neutrons creates an isotope. Changing protons creates a different element.
Clickable periodic table
Select any of the 118 elements without typing another input.
MetalsMetalloidsNonmetals and noble gases
How to useSelect one element, refine the isotope and ion charge when needed, then review the atomic structure using the correct chemistry relationships.
Select an elementType its name, symbol, or atomic number, or choose it from the periodic table.
Choose an isotopeKeep the suggested mass number or enter an exact isotope mass number.
Set ion chargeUse zero for a neutral atom, positive for lost electrons, or negative for gained electrons.
CalculateReview protons, neutrons, electrons, notation, shells, and periodic position.
Use the resultPreview, print, or save the complete chemistry report; verify laboratory, safety, or important decisions with authoritative scientific references.
What your result meansThe dashboard separates the properties that define an element from the properties that can change when an isotope or ion is selected.
Element identityAtomic number 11 fixes the proton count at 11.
Periodic positionPeriod 3, group 1, s-block.
Outer electronsOne outer-shell electron in the neutral atom.
Common oxidation states−1, +1
Typical contextSodium compounds are central to chemical manufacturing, lighting, heat transfer, and biological electrolytes.
Across a period
Atomic radius generally decreases while ionization energy and electronegativity generally rise, with important exceptions.
Down a group
Additional electron shells generally increase atomic size and can change reactivity and metallic character.
Sodium trend snapshot
Its measured properties can be compared with neighboring elements using the report table.
FormulaAll particle counts are integer relationships. Standard atomic weight is displayed separately and is not silently rounded into a mass number.
Protons
p = Z
Neutrons
n = A − Z
Electrons
e = Z − q
Mass number
A = p + n
Example: Sodium-23 with charge +1 has 11 protons, 12 neutrons, and 10 electrons.
Tips and common mistakesUse the calculator as an educational structure model and keep isotope data, atomic weight, and chemical hazards conceptually separate.
Useful tips
- Enter an integer isotope mass number when you need an exact neutron count.
- Use a positive charge when electrons are lost and a negative charge when electrons are gained.
- Compare the neutral and ion diagrams to see which particle count changes.
- Use the highlighted group and period to study periodic relationships.
- Verify isotope stability and laboratory properties in an authoritative database.
Common mistakes
- Treating standard atomic weight as the exact mass number of one isotope.
- Adding a positive ion charge to the electron count instead of subtracting it.
- Changing the number of protons when creating an ion.
- Assuming every oxidation state represents a stable monatomic ion.
- Treating a simplified shell diagram as a complete quantum-mechanical model.
Worked examplesThree familiar cases show how isotope mass and charge affect the result without mixing in unrelated chemistry calculations.
Chlorine-35, Cl⁻
n = 35 − 17 = 18
e = 17 − (−1) = 18
e = 17 − (−1) = 18
The ion gains one electron; its atomic number and proton count remain 17.
Carbon-12 and Carbon-14
C-12: 6 neutrons
C-14: 8 neutrons
C-14: 8 neutrons
Both are carbon because both have six protons. Their neutron counts and stability differ.
Frequently asked questionsAnswers focus on the selected element, isotope, ion, and periodic-table result.
It calculates protons, neutrons, electrons, isotope-and-ion notation, a simplified shell distribution, periodic position, and selected atomic properties for one element.
Protons equal atomic number. Neutrons equal mass number minus atomic number. Electrons equal atomic number minus the signed ion charge.
Mass number is an integer for one isotope. Standard atomic weight generally represents isotope-abundance information for normal materials and may be a decimal or interval.
No. Forming an ion changes electrons, not protons. Atomic number and element identity remain unchanged.
Isotopes share the same proton count but have different mass numbers, so their neutron counts differ.
Period identifies the horizontal row, group identifies the vertical family when assigned, and block describes the subshell type associated with the element’s position.
It is a simplified educational Bohr-style view. Electron configuration and ion formation can require more detailed quantum-mechanical treatment, especially for transition and inner-transition elements.
No. It identifies particle counts. Stability, half-life, decay mode, and abundance should be checked in an isotope database.
References and data notesElement values should be reviewed against current authoritative releases before laboratory, regulatory, or publication use.
- IUPAC Periodic Table of Elements — names, symbols, atomic weights, and official table context.
- NIST Periodic Table: Atomic Properties — critically evaluated atomic-property references.
- PubChem Periodic Table — interactive element-property reference and linked records.
- Royal Society of Chemistry Periodic Table — educational trends and element context.
- CIAAW Standard Atomic Weights — standard atomic-weight tables and explanatory notes.
- PeriodicTableOfElements.org API — embedded 118-element property dataset used for this implementation; no live request is required.