Reversible Reactions Flashcards

All 6 cards in this deck

What is a reversible reaction?

A reaction in which the products can react to produce the original reactants.

What does the symbol $\rightleftharpoons$ mean in an equation?

e.g. $\mathrm{NH_4Cl} \rightleftharpoons \mathrm{NH_3} + \mathrm{HCl}$

The reaction is reversible — it can go in both directions.

e.g. ammonium chloride breaks down into ammonia and hydrogen chloride, which can recombine.

True or false? The direction of a reversible reaction can be changed by changing the conditions.

True. Changing conditions such as temperature can make the reverse reaction happen.

What is observed when blue hydrated copper sulfate is heated?

It turns white (anhydrous copper sulfate) and water is driven off as vapour.

How can white anhydrous copper sulfate be changed back to blue?

Add water — the reverse reaction forms hydrated copper sulfate, which is blue.

What happens when solid ammonium chloride is heated in a tube, and then the vapours cool?

On heating it decomposes to ammonia and hydrogen chloride gases; on cooling these recombine to form solid ammonium chloride.