When people ask, "What's the mass of hydrogen?" the answer isn't a single number. It really depends on what you're measuring—a single atom, the gas you'd put in a tank, or an industrial-sized shipment. The numbers can be mind-bogglingly...
When someone asks about the weight of hydrogen gas, what they're really trying to figure out is its density. While the exact value shifts with temperature and pressure, we have a standard benchmark to start from. At standard temperature and pressure (STP),...
