February 2025

The digestion process

By |2025-02-12T09:20:39+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

digestive_system_-min The digestive system of a human being. Image credit MediaWiki ZIMSEC O Level Combined Science Notes: The digestion process

  • Food is broken down in the alimentary system from large pieces/molecules into smaller molecules.
  • The food most mammals ingest is in large pieces e.g. leaves, grass, cake, meat etc.
  • All […]
Comments Off on The digestion process

Diffusion and Osmosis experiments: Visking Tubing/Egg membrane

By |2025-02-12T09:05:48+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

A person tying the visking tubing. Image credit YouTube. A person tying the visking tubing. Image credit YouTube. ZIMSEC O Level Combined Science Notes:Diffusion and Osmosis experiments

Aim: Create a membrane model for molecules and their movement.

Materials

Visking tubing/egg membrane, string, beaker, 20% sugar solution, weighing balance, water.

Method A

Comments Off on Diffusion and Osmosis experiments: Visking Tubing/Egg membrane

The differences between wind and insect pollinated flowers

By |2025-02-12T09:26:15+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Maize flower close up. image credit freeimagescollection.com Maize flower close up. image credit freeimagescollection.com ZIMSEC O Level Combined Science Notes: Reproduction in plants: The differences between wind and insect pollinated flowers

  • Not all flowers are  exactly the same
  • Some flowers have adapted to be pollinated by wind
  • Others have adapted in a way […]
Comments Off on The differences between wind and insect pollinated flowers

Experiment: Testing the infiltration capacity of soils

By |2025-02-12T09:44:29+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Testing infiltration in soils Testing infiltration in soils ZIMSEC O Level Combined Science Notes: Testing the infiltration capacity of soils

Materials: Tins with their tops and bottoms removed, water

Method

  1. Gently push the tins into the ground, make sure that they are in different soil types
  2. Pour 100ml of water into the cylinders and measure […]
Comments Off on Experiment: Testing the infiltration capacity of soils

Molecules

By |2025-02-12T09:07:27+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Molecules of carbon, oxygen, hydrogen and water Molecules of carbon, oxygen, hydrogen and water ZIMSEC O Level Combined Science Notes: Molecules

  • A molecule is the smallest particle of a compound formed when atoms of elements combines
  • The atoms combine together by forming bonds
  • When these bonds are formed there are energy changes
  • Typically heat energy […]
Comments Off on Molecules

Experiment: The reaction of metals with dilute Hydrochloric acid

By |2025-02-12T09:41:04+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Copper does not react with hydrochloric acid. Image credit fphoto.com Copper does not react with hydrochloric acid. Image credit fphoto.com ZIMSEC O Level Combined Science Notes:  Experiment: The reaction of metals with dilute Hydrochloric acid

Aim: To examine the reactivity of metals with dilute hydrochloric acid

Materials: 5 test tubes, dilute hydrochloric acid, magnesium, zinc, […]

Comments Off on Experiment: The reaction of metals with dilute Hydrochloric acid

Experiment: Investigating the neutralisation process

By |2025-02-12T09:10:28+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

ZIMSEC O Level Combined Science Notes: Experiment: Investigating the neutralisation process

Aim: To find out what happens to the pH of an acid when a base is added

Materials: vinegar, plastic beaker, measuring cylinder, stirring rod, spatula/plastic teaspoon, slaked lime (calcium hydroxide), universal indicator paper

Method

  1. Place about 10 cm3 of vinegar in a beaker
  2. Dilute it with an equal volume of water
  3. Remove […]
Comments Off on Experiment: Investigating the neutralisation process

Purification of copper using electrolysis

By |2025-02-12T09:27:29+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Electrolysis of copper. Image credit 180daysofteaching.wordpress.com Electrolysis of copper. Image credit 180daysofteaching.wordpress.com ZIMSEC O Level Combined Science Notes:Purification of copper using electrolysis

  • The impure copper (blister copper) yielded from the converter
  • Is then molded into thick sheets
  • These sheets become positive plates i.e.
  • they are connected on the positive side […]
Comments Off on Purification of copper using electrolysis
Go to Top