The units of density depend on the units used for mass and volume. The most commonly used units are grams per cubic centimetre (g/cm³) or kilograms per cubic metre (kg/m³). These balloons are the same ...

A nanoporous material that holds hydrogen at twice the density of cryogenic liquid H2 could address the challenges of large-scale liquid and gas storage that have held this clean fuel back. Hydrogen ...

Everything around you - and even your body - is made up of the three phases of matter. Let's find out more. The whole world and everything we can see around us is made up of matter. Matter can be ...