Unit 14 - Equilibruim and nitrogen

Equilibrium will shift towards the side with fewer molecules

Equilibrium will shift towards the endothermic side

When the reversible reaction happens at the same rate in both direction. No overall effect

By heating hydrated copper(II) sulphate (blue) it removes the water. Anhydrous copper sulphate is white and can be rehydrated

When heated, ammonium chloride decomposes into ammonia and hydrogen chloride. The visible effect of this reaction is that the compound becomes a gas, when the gases cool they crystallise into their original form of solid ammonium chloride

Add aqueous sodium hydroxide Identify the gas evolved, if it’s ammonia then the test is positive

Turns damp red litmus paper blue Pungent smell Stopper of concentrated hydrochloride acid produces a white smoke

Nitrogen (from air) and hydrogen (from natural gases or cracking of hydrocarbons). These are passed over an ion catalyst at 200 atmospheric pressure at 450 degrees. The reaction is reversible and exothermic with a yield of about 15%. This mixture is cooled and liquified to allow any unused hydrogen and nitrogen to be recirculated

Manufacture of nitric acid To make fertilisers

In car engines, the temperature reached is high enough to allow nitrogen and oxygen from air to react, forming nitrogen oxides