How to Learn the Ion Charges
When atoms form ions, they gain or lose electrons to reach a stable charge — and for the main groups, the periodic table predicts it. Learn the pattern and you can write correct formulas without a chart. This deck teaches the group charges plus the key transition metals.
There are 13 cards in the deck below. You can read through them, practise them right here with the flip-card player, and then save the deck to study properly with spaced repetition — the method that makes them stick for months, not minutes.
Why the common ion charges is hard to memorize (and the fix)
The main-group pattern is learnable, but the transition metals break it (iron can be +2 or +3), and those exceptions must be memorized separately.
The fix is active recall plus spaced repetition. Instead of re-reading the list (which feels productive but barely works), you test yourself — pull each answer out of memory — and you review each card on a schedule that stretches over time. Every time you successfully recall a fact, the memory gets stronger and the next review is pushed further out. That's how you go from "I saw it once" to "I just know it."
The fastest way to learn the common ion charges
- Break it into small batches. Learn the main-group pattern first (groups 1, 2, 13, 15, 16, 17), then memorize the common transition-metal charges.
- Test, don't re-read. Look at the question, say the answer out loud before flipping the card. The little struggle to recall is what builds the memory — a smooth re-read does almost nothing.
- Review on a schedule. Spaced repetition shows you each card right before you'd forget it. Get one right and it comes back in a few days, then a week, then a month. Miss one and it comes back sooner.
- Keep sessions short and daily. Five to ten minutes a day beats a two-hour cram every time. Consistency is the whole game.
One fact per card. Roman numerals in a name give the charge for transition metals: iron(II) is Fe²⁺, iron(III) is Fe³⁺.
The full deck: the Ion Charges
Here's every card in the set. Practise them above, or save the deck and let spaced repetition schedule your reviews automatically.
| Element / group | Ion charge |
|---|---|
| What charge do Group 1 metals form (Na, K)? | +1 |
| What charge do Group 2 metals form (Mg, Ca)? | +2 |
| What charge does aluminium (Group 13) form? | +3 |
| What charge do Group 15 elements form (N, P)? | −3 |
| What charge do Group 16 elements form (O, S)? | −2 |
| What charge do Group 17 halogens form (Cl, F)? | −1 |
| What charge does sodium form? | +1 (Na⁺) |
| What charge does oxygen form? | −2 (O²⁻) |
| What charges can iron form? | +2 (Fe²⁺) or +3 (Fe³⁺) |
| What charge does zinc form? | +2 (Zn²⁺) |
| What charge does silver form? | +1 (Ag⁺) |
| What charge does copper commonly form? | +2 (Cu²⁺) or +1 (Cu⁺) |
| Do metals form positive or negative ions? | Positive (they lose electrons) |
Save this deck and actually remember it
Create a free account, keep this 13-card deck, and we'll schedule every review at the perfect moment. First deck free forever — no credit card.
Study this deck free →FAQ: learning the common ion charges
How long does it take to learn the common ion charges?
Most people can lock in the common ion charges within one to three weeks of short daily sessions. With spaced repetition doing 10–13 cards a day, you'll recognise them within days and recall them reliably within a couple of weeks.
What's the best way to memorize the common ion charges?
Active recall plus spaced repetition. Test yourself instead of re-reading, and review on a schedule that spaces the cards out over time. Flashcards are built for exactly this — which is why the deck above is the fastest path.
Is this deck free?
Yes. You can practise all 13 cards on this page for free with no account. Sign up (also free) to save the deck and let spaced repetition schedule your reviews so it sticks long-term.