At a glance
- Problem
- Students need chemistry tools that show their arithmetic and units without requiring an account.
- My contribution
- I designed, built, and operate browser-based calculators and reference material with visible steps and units.
- Outcome
- A live, advertising-supported product with worked calculations, unit converters, and a periodic table covering all 118 elements.
Engineering decisions
01decision
Show the arithmetic
One connected workflow carries a formula through molar mass, solute mass, moles, final solution volume, and molarity. An optional stronger stock concentration adds a C₁V₁ = C₂V₂ dilution calculation.
02decision
Keep calculations in the browser
Interactive calculators and converters respond locally and require no account. URL-based inputs make supported calculations shareable.
TradeoffNo accounts means no saved history; a calculation is shared by its URL or printed worksheet instead.
03decision
Make assumptions part of the answer
Worked steps retain units and small values instead of rounding them to zero. The worksheet states its complete-dissolution, purity, and volume assumptions, and distinguishes formal concentration from individual ion concentrations.
What you can verify
- Live calculators, unit converters, and a periodic table covering 118 elements.
- A worked NaCl preparation connects the element breakdown to concentration and optional dilution.
- Share the inputs by URL or print a worksheet with the calculation and assumptions.
Source and release links checked .
Scope and limits
Educational calculations depend on the calculator's assumptions and reference values. The site is free and supported by advertising; it is not a validated laboratory or clinical decision system.
A short walkthrough
- 01
Enter NaCl, a solute mass of 5.844 g, and a final solution volume of 250 mL.
- 02
Check the 0.100000 mol and 0.400000 mol/L result, then enter a 1 mol/L stock concentration.
- 03
Inspect the 100 mL stock calculation and share or print the worked steps with their assumptions.