Memojin
Equations, mechanisms, nomenclature

Chemistry demands exactness.

One coefficient out of place and the equation means nothing. Memojin keeps subscripts and arrows where they belong, and turns nomenclature — the part everyone thinks they know and misspells in writing — into short questions that keep coming back.
Formula
Balanced equation for the combustion of dihydrogen
balanced: two molecules of water formed
The problem

You know which reaction happens, but you write it down wrong.

This subject forgives nothing approximate: a misplaced subscript changes the molecule, a forgotten coefficient breaks the balance. And that is exactly the sort of detail passive reading never catches.
Equations keep their shape
H two O stays H two O, the arrow points the right way, physical states hold as subscripts. Nothing flattens into plain text.
Fill-in-the-blank for numerical values
A half-known Avogadro number is invisible while rereading; masked in the middle of a sentence, it shows itself at once for what it is.
Nomenclature in small doses
Family names, suffixes, functional groups: many very short items, revisited often, rather than one list swallowed whole.
From your notes to cards

A chapter of reactions, three cards.

Each card shape takes on a different kind of mistake.
Uploaded excerpt · reactions and amounts
The combustion of dihydrogen in dioxygen produces water. A mole corresponds to a fixed number of elementary entities. The pH measures the acidity of a solution on a logarithmic scale.
gives
Formula
Balanced equation for the combustion of dihydrogen
balanced: two molecules of water formed
Fill in the blank
A mole contains … elementary entities.
6.02 × 10²³
Two-sided
What does the pH of a solution measure?
The hydrogen ion concentration, on a logarithmic scale.
The right shapes

The shapes that pay off in chemistry

Three shapes, three different mistakes caught.
Formula
The only one able to carry a balanced equation without distorting it, coefficients and subscripts included.
Fill in the blank
It isolates the exact value inside a familiar sentence, and exposes what you only thought you knew.
Two-sided
For definitions and roles: one question asked, one answer to produce in full.
Your sources

What becomes cards

The textbook chapter, the nomenclature sheet, the practical write-up: anything carrying text will do.
PDF
A chapter, a handout, a past paper with answers.
Word
Your own notes, in .doc as well as .docx.
PowerPoint
The lecture deck, exactly as you were given it.
Photo of your notes
The whiteboard or your notebook, as JPG or PNG.
YouTube video
An online lecture, straight from its address.
Pasted text
Three paragraphs are enough to make a deck.
Anki import
Your old deck finds its place again, in its own window.
On exam day

As the test approaches

With the date set, revision concentrates on what still resists and eases off what is secure. Days marked as holidays in the calendar stay empty. The method, in detail →

Frequently asked questions

Do chemical equations display correctly?

Yes: since the notation is typeset, subscripts stay subscripts and the reaction arrow keeps its shape. An equation read on the card looks like the one on the board.

Can reaction mechanisms be revised?

Yes, by cutting them step by step. Each step becomes a card, and the sequence becomes another: that is how a mechanism is retained, not by contemplating the whole scheme.

What about the periodic table?

It yields a very large number of short cards — symbol, number, family. It is the textbook case of what spaced repetition does and rereading does not.

My structural formulas are drawn by hand.

Photograph the page: the image becomes the support for the question, and you answer by naming the molecule or its functional group.

A badly balanced equation is not rescued by the mark scheme.

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