# Measurement and the Metric System

## Atmosphere Bar

The end of a long aluminum bar exerts 14 psi.

## Conservation of Mass

Flashbulb weighs the same before and after ignition.

## One In A Million

A transparent globe filled with about a million nonpariels.

## Liter Cube

A wooden cubic decimeter is cut up into cubic millimeters.

## Density

Containers filled with equal volumes of substances of varying densities.

## Volumetric Glassware

A collection of various devices used to measure volume in the lab.

## Counting Units

A pairs, a dozen, a six-pack, a gross, and a ream are used to introduce the mole.