A newer version of Solve-ent is ready. It will be used next time you open this, or you can switch to it now.
Before you start
This is practice for the algebra a chemistry calculation needs — rearranging a formula, using a ratio, moving powers of ten, cancelling units, and keeping the right number of figures. Seven kinds of move, and nothing else.
It does not solve the question for you. There is a calculator in the bar at the top, on every screen, because you should not need a second thing in front of you to work out a number — but choosing what to multiply, and which way up to put it, is the whole of what this is for and it never does that part. Free tools already work these out and already show the steps. What this does instead is look at a wrong answer and work out which mistake produces that exact number — the ratio used upside down, the exponent multiplied instead of raised, a conversion factor turned the wrong way — and tell you that.
And it refuses to guess. When two different mistakes would produce answers nobody could tell apart, it will not ask that question at all. When it cannot work out what happened, it says so rather than picking something that sounds likely.
Nothing you type is sent anywhere. There is no account, no sign-in and nothing stored about you.
The name is a pun: solve, and solvent. That is the only time it will be mentioned.
What do you want to work on?
Pick one. Five questions, one step at a time. Nothing is recorded and nothing is scored.
Or do a set somebody has given you
If you were given a key and a number, this is where they go. At the end you get a code to hand back, and that code is the only thing that leaves the device.
Or practise one move on its own
If one particular step is the one going wrong, doing whole questions makes you walk past it four times to reach it once.
There is a set here that was not finished
Carrying on picks it up at the step it stopped on, with everything already done still counted. Starting something else forgets it, and there is no way back to it after that.
A set somebody has given you
The key decides which questions you get, so everybody working from the same key gets the same set. The number is the one you were given — it is the only thing about you this app ever holds, and it is not a name.
Pick how the questions are set. All of them are here from the start, none of them is locked, and switching between them changes what the questions ask for and nothing else.
Which move do you want to practise?
The same move, over and over, until it is yours. Whole questions make a move stick once you have it; a move you do not have yet is built by doing it again.
Nothing here is recorded and there is nothing to hand in.
What you have so far on this question
That is the end of the set
The code for this set
Write it down exactly as it is, including the dashes. It says which number you are, how many steps you did, how many were right first time, and where the wrong ones were — and nothing else about you.