Hand in Hand

What this book is about

Salt dissolves. Diamond does not scratch. Water climbs up a plant against gravity. Oil refuses to mix with anything. Two strands of DNA hold onto each other for a lifetime and then let go at exactly the right moment. Every one of those facts is the same fact, seen from a different angle — and the fact is about electrons deciding how to share.

This book is about that decision. It starts with a single atom and the outermost electrons it can spare, borrow or hold on to, and from there builds the whole vocabulary of chemistry: ionic bonds, covalent bonds, metallic bonds, and the weaker attractions that nobody mentions at school but that quietly run biology.

The approach is the same as the rest of the series. Nothing is asserted that cannot be pictured. Bonds are shown as hands — gripped, shared, loosely touching — and the metaphor is pushed until it breaks, at which point the book tells you it has broken and gives you a better one.

By the end, a reader who started with "atoms join together somehow" can look at a substance and make a real prediction: will it melt easily, will it dissolve, will it conduct, will it be hard or soft — and say why.

What is inside

• The atom's outer shell, and why eight is such a popular number
• Ionic bonds: giving and taking, and why salt is a cube
• Covalent bonds: sharing, single and double, and the shape of water
• Metallic bonds, and why metals bend instead of shattering
• The weak forces — hydrogen bonds and the rest — and why life depends on them
• Activities, a bilingual glossary, a quiz and the sources

The English edition, Hand in Hand, carries the same 97 pages and the same figures.