Hydrogen, Nitrogen and Ammonia

Hydrogen

— light gas → not in earth's atmosphere

— can be found in space

— fuses with each other in the sun to form helium atoms → energy given out as light and energy

Making in the lab

— by using a more reactive metal to displace it from dilute acids

e.g. Zn + H2SO4 → ZnSO4 + H2

Properties

— light → 20 times lighter than air

— colourless, odourless

— reacts with oxygen to form water (can be explosive)

— displaces copper, silver, and gold

Nitrogen

— 78% of air

— consumed from food as proteins

• used to build → muscles, hair, skin, bone, blood, tissues

Properties

— colourless, odourless

— slightly soluble

— unreactive compared to oxygen

— forms ammonia: N2 + 3H2 → 2NH3