CHEMISTRY
(На русском: Пособия по химии)
On this page you can find a table of conversion of chemical concentrations, I've done for myself to use in school and in university. It's very useful.
There is also a formulas for calculating the concentration of the mixture of the two solutions and calculating the concentration of the alloy on that page.
You can also view and download properties of chemical elements in digital form.
On another site you can see a photo of my collection of chemical elements.