Lesson 01 · Read the clues
Every guess
tells you something.
You do not need to memorise the whole table. Learn what each clue means, then combine the clues to narrow your next guess.
Start with the direction.
In Elemendle, the arrow tells you where the answer’s value is relative to your guess. It does not tell you whether your guess was good or bad.
Exact match
Keep this property.
Target is higher
Look for a larger value.
Target is lower
Look for a smaller value.
Block, type and phase have no higher or lower direction: they either match or differ. A matching property is one useful clue, not necessarily a solved puzzle.
Two numbers, two different ideas.
Atomic number: the element’s identity
Atomic number counts the protons in an atom’s nucleus. Carbon has 6; oxygen has 8. The table follows increasing atomic number.
Game example: you guess oxygen (8) and see ↑ for atomic number. Keep elements numbered above 8. A later ↓ from calcium (20) would narrow that to 9–19.
Atomic mass: not another name for atomic number
For many elements, the decimal mass on a periodic table reflects the relative abundances of their isotopes. It is not a proton count. Some radioactive elements are shown with a representative isotope’s mass number instead.
In the game, compare the displayed mass values separately. Do not assume mass always increases with atomic number: argon is number 18 but has a greater standard atomic weight than potassium, number 19.
Find the row and the column.
A period is a horizontal row. A group is a vertical column, numbered 1–18. Elements in a group often share chemical characteristics.
SodiumMg
MagnesiumPeriod 4 →K
PotassiumCa
Calcium
For a numeric group or period clue, ↑ means a larger group or period number. A period increase moves down the table. Use the numbers rather than interpreting ↑ as “move upward on the page”.
Use categories to cut down the list.
Block
The s, p, d and f blocks describe regions associated with electron subshells. In this game, a block match keeps that region in play. Block and group are different labels; helium is in group 18 but belongs to the s block.
Element type
Labels such as alkali metal, alkaline earth metal and noble gas describe categories. Magnesium and calcium are both alkaline earth metals. A type match helps you recognise a family, but you still need other clues.
Phase
Phase tells you whether the element is listed as solid, liquid or gas at the game’s reference conditions (STP). Temperature and pressure matter; a phase label is not a claim that a substance always stays in that state.
If a property is shown as unknown or has no numeric group, do not invent a value. Use the remaining clues. A classification in the game is a clue from its dataset, not a complete account of an element’s chemistry.
A fixed practice example
From magnesium to calcium.
Imagine the hidden answer is calcium and you guess magnesium. This teaching example is independent of today’s puzzle.
| Clue | Your guess: Mg | Feedback |
|---|---|---|
| Atomic number | 12 | ↑ Target higher (Ca: 20) |
| Period | 3 | ↑ Target higher (Ca: 4) |
| Group | 2 | ✓ Exact |
| Block | s | ✓ Exact |
| Type | Alkaline earth metal | ✓ Exact |
| Phase | Solid | ✓ Exact |
- Keep group 2 elements: that column matches.
- Look beyond period 3 and atomic number 12.
- Calcium fits those conditions, making it a sensible next guess. Heavier group 2 elements can also fit these clues, so the row alone does not prove calcium is the answer.
Try one before the quiz: what if magnesium’s period showed ↓?
The target would have a period number below 3. If group 2 still matched, beryllium in period 2 would fit those two clues.
Your turn: read three clues.
Choose an answer, then check the reasoning. Nothing here changes your daily score or streak.
Question 1 of 3
Your guess has atomic number 8. The feedback is ↑. What does that tell you?
Build your element vocabulary.
Want to recognise more of the names behind the clues? Start with hydrogen through calcium.
Meet the first 20 elements →Sources & further reading
- OpenStax: how the periodic table is organised
- American Chemical Society: atomic number and atomic mass
- Royal Society of Chemistry: element data, blocks and physical states
Original examples and questions by Elemendle. Game feedback descriptions follow Elemendle’s comparison rules.