Chemistry in Food & Farm
Discover fertilizers, pesticides, and food preservatives.
Setting up the bench…
What this lesson covers
Why it matters
A pinch of the right chemical makes wheat grow taller; another keeps bread mould-free for a week. The farm and the kitchen both run on chemistry.
Predict first
Why do farmers add fertilisers to the soil?
Fertilisers feed crops the nutrients (nitrogen, phosphorus, potassium) they need; preservatives stop the microbes that spoil food.
- To make the soil look colourful
- To supply nutrients like nitrogen that plants need to grow — correct
- To kill every insect instantly
What you do
Sort each one by its job on the farm or in the kitchen.
Check yourself
Why add fertiliser to a field?
Plants need nitrogen, phosphorus and potassium; fertilisers supply what the soil lacks.
How does salt help preserve pickles?
Salt (and sugar) draw water out of microbes so they can't grow — the food keeps longer.
- To give plants the nutrients they need to grow — correct
- To make the soil pretty
- To freeze the soil
- It stops the microbes that spoil food — correct
- It feeds the vegetables
- It adds bright colour