Find gold's charge in the mining ion Au(CN)2-.
Two CN- give -2; overall charge is -1; so Au = +1. Heap-leach mining runs on this exact ion — dilute cyanide coaxing gold, atom by atom, into its rare +1 state.
What Is the Charge of Gold?
Gold commonly forms Au+ Au3+ in introductory ionic compounds.
When gold reacts at all, it prefers +3 (AuCl3, chloroauric acid HAuCl4) with +1 in specific partnerships (gold-thiol chemistry, Au(CN)2- in mining). Its resistance to every single acid — only the aqua regia combination dissolves it — is why treasure survives shipwrecks.
| Element | Gold |
|---|---|
| Symbol | Au |
| Atomic number | 79 |
| Common ionic charge | +1, +3 |
| Common ions | Au+, Au3+ |
Visual reference
Gold element image and atomic model
Images are used as visual references; charge rules still depend on the compound.
Where Gold's charge options come from
Gold is [Xe]4f14 5d10 6s1. Relativistic contraction grips its 6s electron ferociously — the same physics that colors gold yellow — making ionization brutally expensive. When forced, losing three electrons to d8 Au3+ (square-planar, like platinum's +2) beats the shallow d10 comfort of Au+, which survives mainly with soft partners like cyanide and sulfur.
This is a classroom reference range, not an exhaustive list of all oxidation states.
The trap in Gold problems
Writing 'gold doesn't react' as an absolute. Aqua regia dissolves it (nitric acid oxidizes a whisper of Au3+, hydrochloric traps it as AuCl4-), and cyanide solutions with air produce Au+ complexes — the basis of a century and a half of gold mining. Nobility has two well-mapped exceptions.
Worked example: Au in a formula problem
Au+ and Au3+ in real compounds
AuCl
Gold chloride
Au+ balances chloride ions.
Au2O
Gold oxide
Gold can form oxides where total positive and negative charge balances.
Questions students ask about gold
Why is gold yellow when silver is white?
Relativity again: gold's compressed orbitals absorb blue light where silver's don't. The same orbital contraction that guards its electrons paints the metal — charge chemistry and color share one cause.
What are gold nanoparticle colors about?
Charge-0 gold spheres nanometers wide glow ruby red in suspension (medieval stained glass, pregnancy test lines) — conduction electrons sloshing in resonance, no ions required.
Does the body handle any gold charges?
Rheumatoid arthritis was long treated with Au+ thiol drugs like auranofin — the soft +1 ion binding protein sulfurs. Metallic gold in teeth and jewelry stays 0 and inert.
How do I use this charge in formulas?
Combine positive and negative ions so the total charge is zero — or let the ionic compound calculator do the crossing for you. The full chart lives on the periodic table with charges.
Where this data comes from
Charges and element facts on this page are checked against the primary references below. Found an error? Email hello@periodictablewithcharges.com — corrections ship in the next content update. See how this site is edited.