General Knowledge Contents

Desalination removes dissolved salts and other substances from seawater or brackish water to produce water suitable for a defined use. Reverse osmosis forces water through a membrane that rejects much of the salt, while thermal me

Historical maps are evidence created for particular purposes, audiences and authorities. They can show routes, settlements, property, terrain and political claims, but they do not simply preserve everything that existed in a place

Census records are government-created sources designed to count and describe a population at a particular time. Historians use them to reconstruct households, occupations, migration and neighbourhood change, but the entries are no

To compare countries in a geography essay, organise evidence around a shared question rather than writing two separate country descriptions. Use indicators with the same definition, unit and year; explain how scale and physical se

A fair scientific comparison tests a defined difference while keeping other important conditions as similar as practical. It does not mean that every object, person or place must be identical. Instead, the design makes the groups

Froth flotation is a mineral-processing method that separates selected mineral particles from unwanted rock by changing how their surfaces interact with water and air. Finely ground ore is mixed with water and carefully chosen rea

A topographic map shows the shape and height of the land on a flat surface, usually using contour lines. Each contour joins points at the same elevation, so the pattern of lines reveals hills, valleys, ridges and steep slopes. Topographic maps also show roads, rivers,.

Critical minerals are materials considered important to an economy or strategic industry whose supply could be disrupted. They are used in products ranging from electric vehicles and power networks to electronics and defence equipment. Their geopolitical importance does not.

Submarine internet cables are fibre-optic communication links laid across the seabed between countries and continents. They carry most international data traffic, supporting video calls, banking, business systems, research and everyday online services. Although satellites.

Earthquake early warning systems detect an earthquake after it begins and try to alert people before the strongest shaking reaches them. They use networks of seismic sensors to identify the first arriving waves, rapidly estimate where shaking may be dangerous and send.

Ice cores are long cylinders of ice drilled from glaciers and ice sheets. Their layers preserve evidence of past snowfall, temperature, volcanic eruptions, dust and the composition of the atmosphere. Tiny bubbles can contain samples of ancient air, while differences in the.

Coastal upwelling is the rise of deeper ocean water towards the surface, often when winds move surface water away from a coastline. The rising water is usually colder and richer in nutrients than the surface layer, helping phytoplankton grow and supporting productive marine.