In I/GCSE Chemistry, we will learn about reversible changes .
Brief intro
Changing the temp. of tubes containing nitrogen compounds:
- Heating --> nitrogen dioxide (NO2) gas forms-->Colour of solution changes to dark brown
- Cooling --> nitrogen tetroxide (N2O4) gas forms-->Colour of solution gets paler
Refer to I/GCSE Chemistry, Water and ice are at a dynamic equilibrium because the rate of freezing = rate of melting. They are also reversible reactions.
Controlling the PH of shampoo protects skin and eyes.
Reversible changes 4A
Molecular collisions
Irreversible change- products can’t form back into the original products
E.g. methane--> (combustion) -->Carbon dioxide + water = irreversible
Reversible- when products can react to produce the original reactants e.g. Evaporation, melting
- Depends upon conditions;
Example of RR
- Heating ice--> liquid
- Water cools to below 0 degrees Celsius
- Ice reforms
When it comes to I/GCSE Chemistry,
Forwards reaction= reactants make more products
Backwards reaction= products make more reactants
Temperature and concentration affects direction of change:
- When the concentration of REACTANTS is higher, it is more likely for the reactants to collide (as there are more of them), and produce lots of products. Thus the FORWARDS reaction is more likely.
- When the concentration of PRODUCTS is higher, it is more likely that the products will collide with each other and decompose to produce lots of the original reactants. Thus the BACKWARDS reaction is more likely.
- When heat is added to the reactants, they have an advantage and will thus . This is the forwards reaction.
- When heat is added to the products, the products have the advantage and will thus produce reactants at a higher rate than the reactants are producing the products at. This is the backwards reaction.
You got it now!
