Beyond the answers - interesting background to this quiz

The Nile is more than an Egyptian river

The Nile is often associated almost exclusively with Egypt, but its drainage basin is remarkably wide. It flows through or along the border of several countries in eastern and northeastern Africa. Rwanda, one of the correct options in this quiz, is part of that wider basin through the Kagera River system, which is considered a remote source of the Nile. This connection surprises many people because Rwanda lies far south of the more famous Egyptian stretch.

Nitric acid is a key industrial chemical

Nitric acid, with the formula HNO3, is one of the most widely produced acids in the world. It is essential in the manufacture of fertilisers, particularly ammonium nitrate, and it also plays a role in producing explosives, dyes, and certain plastics. In concentrated form it is highly corrosive, and it can release toxic nitrogen dioxide fumes. Its importance to agriculture makes it a quiet foundation of modern food production.

Lambert Glacier drains a frozen continent

The Lambert Glacier in East Antarctica is generally considered the largest glacier on Earth. It is a huge ice stream that channels ice from the interior of the Antarctic ice sheet toward the Amery Ice Shelf. While glaciers such as Vatnajökull in Iceland or Perito Moreno in Argentina are more famous and far more accessible to tourists, Lambert operates on a completely different scale, hidden in one of the most remote regions on the planet.

Luanda is a major Atlantic port

Luanda, the capital of Angola, sits on the Atlantic coast of southwestern Africa. It grew from a Portuguese colonial settlement into one of the largest Portuguese-speaking cities in the world. Today it is both the political capital and the economic centre of Angola, with a busy port that has historically been central to the country's oil-driven economy. The city's coastal location distinguishes it from inland capitals such as Kampala or Maputo.

Common salt has a simple but vital formula

Sodium chloride, written as NaCl, is one of the most familiar chemical compounds in daily life. It is essential for human health in small amounts, helping to regulate fluid balance and nerve function. Although it is simple in structure, salt has played an enormous role in human history as a food preservative, a trade good, and even a form of currency in some cultures. Its chemical simplicity hides a deep cultural and economic significance.