Maths & Science

Reading the periodic table made simple: groups, periods and blocks explained, UK vs US numbering, and a method to place any element by atomic number.

How to calculate molecular weight step by step, with worked examples for water, glucose, brackets and hydrates, plus a free molecular weight calculator.

Convert scientific notation to decimal step by step, with worked examples and a free converter tool.

How to solve simultaneous equations step by step using substitution and elimination, with clear worked examples and a free algebra solver.

The 5-12-13 triangle is a right-angled Pythagorean triple. Learn its area, angles, perimeter and the Pythagorean proof, with worked examples.