H2O
Mendeleev example

Water: why shape matters

Water is bent, so its bond dipoles do not cancel. Geometry helps explain polarity.

Mendeleev

Start with the particle story: which protons, electrons or nuclei are changing? Then connect that story to the property you observe.

1

Identify the particles or structure involved.

2

Predict the direction of the effect.

3

Check the explanation against the periodic table or a measured property.

Explore elements → · Core Science →

How to use this page

Start by identifying the quantity, element or phenomenon being studied, then connect it with a concrete situation. A scientific formula becomes much easier to understand once every term and unit has a clear physical meaning.

Mendeleev’s habit: always check the order of magnitude. A calculation can look correct while giving a physically impossible result when a unit has been forgotten or converted incorrectly.