February 2025

The Haber process and the Manufacture of Ammonia

By |2025-02-12T08:57:39+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

 ZIMSEC O Level Combined Science Notes: The Haber process and the Manufacture of Ammonia
  • Sable Chemicals produces ammonia at their Kwekwe plant
  • Ammonia is mainly used to make nitrogen fertilizers such as ammonium nitrate which are used in the agriculture industry
  • Ammonia is made using Hydrogen and Nitrogen
  • Hydrogen is obtained from electrolysis of water and
  • Nitrogen […]
Read More
Comments Off on The Haber process and the Manufacture of Ammonia

Fuel Engines

By |2025-02-12T09:12:54+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Most cars use fuel engine. Image credit ecurrent.fit.edu/blog/ Most cars use fuel engine. Image credit ecurrent.fit.edu/blog/ ZIMSEC O Level Combined Science Notes: Fuel Engines

  • A machine is a device that changes energy from one form to another
  • When the energy used by the machine is chemical energy the machine is called […]
Read More
Comments Off on Fuel Engines

Resistors in parallel and in series

By |2025-02-12T09:28:08+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

fusion_title size=”3″ content_align=”left” style_type=”default” sep_color=”” margin_top=”” margin_bottom=”” class=”” id=””]ZIMSEC O Level Combined Science Notes:  Resistors in parallel and in series [/fusion_title]

  • Resistance in a series can be changed by placing more or less resistors in a circuit
  • The total resistance of resistors depends in the way in which they are arranged in the circuit
  • Resistors can be put in series or […]
Read More
Comments Off on Resistors in parallel and in series

Experiment: Generating electricity

By |2025-02-12T09:44:30+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

A dynamo. Image credit wikihow.com A dynamo. Image credit wikihow.com ZIMSEC O Level Combined Science Notes: Experiment: Generating electricity

Aim: To generate electric current

Materials: dynamo, lamp bulb, copper wires, crank or a set of pulleys and weights to turn dynamo, rubber band

Method

  1. Set up the apparatus with the dynamo on a table, the rubber […]
Read More
Comments Off on Experiment: Generating electricity

Comparing the strength of cylindrical and square tube beams

By |2025-02-12T09:09:42+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Testing the strength of a beam Testing the strength of a beam ZIMSEC O Level Combined Science Notes: Experiment: Comparing the strength of cylindrical and square tube beams

Aim:  To compare the strength of cylindrical and square tubes

Materials: thin cardboard, tin can, sand and glue.

Method

  1. Make a cylindrical tube by rolling a piece […]
Read More
Comments Off on Comparing the strength of cylindrical and square tube beams

Experiment: To compare the shear and tensile strength of sponge rubber and soft wood

By |2025-02-12T09:26:19+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Sheets of made of sponge rubber. Image credit rollsheetrubber.com Sheets of made of sponge rubber. Image credit rollsheetrubber.com ZIMSEC O Level Combined Science Notes: Experiment: To compare the shear and tensile strength of sponge rubber and soft wood

Aim: To compare the shear and tensile strength of sponge rubber and a softwood

Materials: wooden ice-cream […]

Read More
Comments Off on Experiment: To compare the shear and tensile strength of sponge rubber and soft wood

Experiment: Finding conditions necessary for growth of microorganisms

By |2025-02-12T09:19:51+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Mouldy bread and their conditions. Image credit Mouldy bread and their conditions. Image credit wordpress.com ZIMSEC O Level Combined Science Notes: Experiment: Finding conditions necessary for growth of microorganisms

Aim: To determine factors affecting the growth of microorganisms in food

Materials:  3 containers with sterilized lids, brad, milk, burners, drying agent (calcium chloride)

Method

  1. Pour […]
Read More
Comments Off on Experiment: Finding conditions necessary for growth of microorganisms

Rhythm/Natural Family Planning

By |2025-02-12T09:38:33+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Image credit atlantablackstar.com Image credit atlantablackstar.com ZIMSEC O Level Combined Science Notes:Contraception:Rhythm/Natural Family Planning

How it works

  • Various techniques are used:
  • Learn to recognise the fertile periods in the menstrual cycle and avoid sex during that period
  • Several techniques are used to identify this fertile period:
    1. The temperature method is when […]
Read More
Comments Off on Rhythm/Natural Family Planning

Water closet/Flush toilet

By |2025-02-12T09:05:09+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Water Closet. Image credit rakbathware.com Water Closet. Image credit rakbathware.com ZIMSEC O Level Combined Science Notes: Water closet/Flush toilet

  • Is part of the water borne sewage
  • This means that wastes from the toilet are carried by water to a place where it is processed
  • This is very common in urban homes […]
Read More
Comments Off on Water closet/Flush toilet
Toggle Sliding Bar Area
Go to Top