February 2025

Experiment: Determining the best conditions for the production of ethanol

By |2025-02-12T09:09:40+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Fermentation of glucose Fermentation of glucose ZIMSEC O Level Combined Science Notes: Experiment: Determining the best conditions for the production of ethanol

Aim: To determine the best conditions for ethanol production

Materials: 5% glucose solution, 20% glucose solution, yeast, sodium hydroxide solution, mealie meal, dilute hydrochloric acid, thermometer, conical flask, cork, glass tube, test tube, […]

Read More
Comments Off on Experiment: Determining the best conditions for the production of ethanol

Potential difference

By |2025-02-12T09:23:46+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

A voltmeter in a circuit A voltmeter in a circuit measuring potential difference between two points ZIMSEC O Level Combined Science Notes: Potential difference

  • Potential difference is the “electrical pressure” which causes current to flow in a circuit
  • The amount of current flowing depends on the potential difference of the circuit

    • […]

Read More
Comments Off on Potential difference

Lead acid accumulators

By |2025-02-12T09:40:28+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

ZIMSEC O Level Combined Science Notes:  Lead acid accumulators

  • These act as a storage cell
  • Electrical energy is passed into the cells during the charging cycle
  • It is stored in the form of chemical energy
  • \text{Chemical Energy}\xrightleftharpoons[charging]{discharging} \text{Electrical Energy}
  • Lead acid accumulators are known as secondary cells
  • Secondary cells-can be recharged once the voltage drops
  • Charging is done […]
Read More
Comments Off on Lead acid accumulators

Experiment: Demonstrating the effects of short-circuits and overloads

By |2025-02-12T09:06:51+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Demonstrating how fuses work Demonstrating how fuses work ZIMSEC O Level Combined Science Notes: Experiment: Demonstrating the effects of short-circuits and overloads

Aim: To demonstrate the effect of a short circuit/overloading of a circuit on a fuse

Materials: 6 or 12 V battery, copper wires, fuse wire/steel wool strand, switch, car headlamp, torch bulb, switch, […]

Read More
Comments Off on Experiment: Demonstrating the effects of short-circuits and overloads

Metal and metal alloy properties and their construction uses

By |2025-02-12T09:21:53+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Metals are popular in construction. Image credit traveldigg.com Metals are popular in construction. Image credit traveldigg.com ZIMSEC O Level Combined Science Notes: Metal and metal alloy properties and their construction uses

  • Metals are popular construction materials
  • They have properties that make them suited for making diverse structures
  • They are ductile which means […]
Read More
Comments Off on Metal and metal alloy properties and their construction uses

Experiment:Finding the mechanical advantage of an inclined plane

By |2025-02-12T09:40:29+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

ZIMSEC O Level Combined Science Notes: Experiment:Finding the mechanical advantage of an inclined plane

Aim: Finding the Mechanical Advantage of an inclined plane

Materials: 1m long plank, sandpaper, bricks. cotton reel, nails, thick steel wire, wood block (smoothed on the underside) weights/tin and sand, pliers, string, spring balance/scales

Finding the mechanical of an inclined plane Finding the […]

Read More
Comments Off on Experiment:Finding the mechanical advantage of an inclined plane

People and Energy

By |2025-02-12T09:15:19+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Construction workers require a lot of energy. Image credit nehandaradio.com Construction workers require a lot of energy. Image credit nehandaradio.com ZIMSEC O Level Combined Science Notes: Experiment: People and Energy

  • While it is true that everyone needs energy for metabolism and daily activities
  • Different people have different food needs
  • Food requirements can […]
Read More
Comments Off on People and Energy

Effects of population growth on natural resources

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

Environmental degradation in Epworth. Image credit newsday.co.zw Environmental degradation in Epworth. Image credit newsday.co.zw ZIMSEC O Level Combined Science Notes: Population and natural resources

Environmental Effects

  • Soil erosion
  • Deforestation
  • Desertification
  • Reduced soil fertility

Social Effects

  • Overcrowding
  • Criminal activities
  • Immorality
  • Poor health services
  • Poor education facilities
  • General increase in poverty

To […]

Read More
Comments Off on Effects of population growth on natural resources

Chlorophyll and Photosynthesis

By |2025-02-12T09:41:18+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

A green leaf. Image credit wallconvert.com A green leaf. Image credit wallconvert.com ZIMSEC O Level Combined Science: Chlorophyll and Photosynthesis

Aim: To test whether chlorophyll is necessary for photosynthesis.

Materials

Two plants with variegated leaves i.e. leaves that are partly green, permanent marker  and equipment for the start test. A [...] </p srcset=

Read More
Comments Off on Chlorophyll and Photosynthesis
Toggle Sliding Bar Area
Go to Top