Chemistry · Chapter 1

Build Any Measurement From Seven Units

Pick one of the seven SI base units, attach a prefix, and type a value. The number line shows how big your measurement really is, and the second panel builds derived units out of the same seven.

How big is it? every tick is a power of ten

Number line of powers of ten with SI prefixes and size references

The red marker sits at the size of your measurement. Prefixes let one short number cover this whole range.

Units built from base units derived units

Base units combining into a derived unit

 

Your measurement

2.50km length
In scientific notation: 2.50 × 103 m
Written out in full: 2500 m
The prefix stands for: 103, one thousand
 

Controls

Base quantity
kilo (k) = 103
Reading the base units
Length is measured in meters
The meter is one of the seven base units. Every length in chemistry, from a bond to a bench, is reported in meters with a prefix.