Everyday Formulas
Salt, rust and vinegar
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You can always create as many flashcards as you like, free of charge.
This deck costs you nothing. You get 36 flashcards, sorted into 4 categories and with notes that add to them. You start out learning instead of typing, and whatever you find missing later you add yourself.
- Cards
- 36
- Categories
- 4
- Price
- free
Free, no account, no ads
What is in this deck
With this deck you learn the chemical formulas of the substances you handle every day: salt, baking soda, sugar, rust and vinegar.
One oxygen atom separates CO₂ from CO, one makes drinks fizzy, the other kills. That is how close these formulas sit.
This deck asks for the substances you meet in the household, at the pharmacy and on an ingredient list. Where two are easily confused, the note says so: baking soda is not washing soda, and limestone shares its formula with marble and chalk.
The formulas are facts; the selection follows what actually sits on the shelf.
The categories decide what comes up: start with “Air and water” alone and add the rest when you are ready.
What you learn
- 36 substances from table salt to antifreeze
- Why CO and CO₂ are not the same
- Baking soda vs washing soda, limestone vs marble
The categories
4 categories sort the 36 cards. You can filter by category and take on what is due right now.
- Air and water
- Body and food
- Household
- Technology and materials
What you get
Here are three of the 36 cards that are in this deck.
Question
What is the chemical formula of table salt?
Answer
NaCl
Note
Chemically sodium chloride. The same salt in the sea, on the roads and on the table.
Question
What is the chemical formula of water?
Answer
H₂O
Note
Question
What is the chemical formula of table sugar?
Answer
C₁₂H₂₂O₁₁
Note
Sucrose, one molecule of glucose plus fructose, split apart again in the body.
Learning with Qardbox
You see a card, you think, you turn it over and say whether you knew it. A round asks nothing more of you, and how the app works out the next date from that is on the page about FSRS-6.
What sits comes back less often, what wobbles comes back soon. You set a daily goal, and when nothing is due the app tells you exactly that instead of inventing work for you. How a round goes is shown on the learning page.
Everything stays on your device. No account, no sign-up, no ads. After the purchase the deck sits in your library like any other subject and can be studied, reordered and extended just like your own.
What it costs, and what it doesn’t
Qardbox itself costs nothing, and it stays that way. Every function is there from the start, with no subscription, no ads and no tiers; what that rests on is on the page about what it costs.
Your own cards stay unlimited, and decks from friends or from the family you read in without a limit, from a file as well. You do not need this deck in order to learn with Qardbox.
This deck costs nothing. Its 36 cards are checked and save you the work you would otherwise have.
Common questions
Do I have to pay for Qardbox?
No. The app is free, with no subscription and no ads, and every function is there. This deck is free too; some other ready-made decks cost a little, once.
Could I make these cards myself?
Yes, without limit and for free. You can type them, import a file or take over cards from friends. This deck only saves you the work.
How many cards are in Everyday Formulas?
36 cards, sorted into 4 categories.
Do I need a connection to study?
Only to download the deck. After that it lives on your device and you study offline. There is no account, and you sign in nowhere.
Which devices does this run on?
On iPhone and iPad from iOS 26, and on Apple Watch. One purchase covers the family through Family Sharing.
Is there a Qardbox for Android?
No. Qardbox is there for iPhone, iPad and Apple Watch, not for Android and not in a browser.
Other decks that go with this one
Get started
Get Qardbox, look at the deck in the store and decide there. The app is free whether you take this deck or not.
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