A Catalyst article about green chemistry. Many reactions take place in solution. Water is a familiar solvent but there are many others, including a rather surprising one, carbon dioxide, which is a non-polluting ‘green’ solvent. The chemical industry relies on solvents to produce many everyday products, such as:...

This Catalyst article looks at 'Restored Hearing', a business which grew out of a school science project. It provides therapy for sufferers of temporary tinnitus, a debilitating hearing condition caused by exposure to loud noises. The article looks at how hearing loss can occur and how also explains how the...

A Catalyst article about how engineers use their understanding of sound waves to develop highly realistic sound systems for films, music systems and computer games. The same ideas can help people with eyesight and hearing problems. Sound waves are affected by their surroundings and the article examines this along...

This Catalyst article looks at the work of Robert Hooke, an employee of the Royal Society, Britain's oldest scientific society. His job was to present two or three different experiments each week to the assembled members of the society – and this was at a time when experimentation was new and there were no books of...

A Catalyst article about high-level nuclear waste. It is hot, corrosive and a source of intense radiation. The nuclear industry is seeking safe ways to deal with such waste, and wants the public to help shape the decisions that are made. This article presents some information about the options for the storage of...

How big?
This resource uses scale models to understand the huge differences between the Sun and other stars in the galaxy. The spreadsheet gives scales for the Sun and five...

A Catalyst article about Hurricane Katrina which caused many deaths in August 2005, and vast damage along the coastline of the Gulf of Mexico in the USA. Hurricanes are an unfamiliar phenomenon here in the UK. Why is this? And can people expect to see more hurricanes in future as a result of climate change? The...

A Catalyst article about hydrogels. Soft contact lenses, disposable nappies, hair gel and plant water crystals all make use of substances called hydrogels. These are polymers which have the unusual property of being able to absorb huge quantities of water. The article looks at the structure of hydrogels and their...

This Catalyst article describes an experiment in which, using a microwave oven, water can be boiled in a cup made of ice, allowing all three states of water to be seen at once. The article explains what equipment needed to carry out the experiment, instructions, and a detailed explanation of why it works.

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A Catalyst article about the discovery of puerperal fever by Ignaz Semmelweis a doctor in a maternity ward in Vienna general hospital. The article looks at his observations into death rates and shows how scientists use observations and theories to make practical changes that can improve life. In the case of...

A Catalyst article about giant asteroids. Astronomers say that, one day, a giant rock from space will collide with the Earth and cause mass devastation. This could lead to the extinction of many species, including humans. The article looks at what can be done to prepare for such an impact and what happened when a...

A Catalyst article about in vitro fertilisation. About one in six couples gets help from specialists because they cannot conceive. One possibility is to use in vitro fertilisation (IVF). ‘In vitro’ means ‘in glass’ and refers to the fact that fertilisation takes place in a laboratory dish or test tube, hence the...

This Catalyst article explains how in nature, bioamplification causes substances to become more concentrated as they move from eater to eaten along a food chain. This sequence occurs in relation to the concentration of pesticides like DDT along a food chain, and causes problems for those animals, like birds of prey...

A National STEM Learning Centre and Network Engineering Case Studies resource investigating the industrial uses of Hemp.

Hemp is making a comeback!

Industrial hemp...

A Catalyst article describing how the VISTA telescope, which is located in Chile, works. It detects infrared radiation - electromagnetic radiation beyond the red end of the spectrum. This has two great benefits:

*The telescope can detect radiation from distant stars which are otherwise hidden behind clouds...