How fast is ‘greased lightning’?
In comic books of the 1950s, one of the favourite phrases of super-heroes such as Superman was ‘greased lightning!’ The idea is one of extreme speed. The lightning we see,…
The SI unit of length
A common problem in Anglo Saxon England, as well as much of contemporary Europe, was the way cloth merchants could so easily cheat the common people. At a market, it…
The practice of thermodynamic measurement
Although the answer to the simple question ‘what is temperature?’ seems obvious at first sight, it is surprisingly difficult to answer to everyone’s satisfaction. In fact, it is generally easier…
Thermal equilibrium and the zeroth law of thermodynamics
A fever is often the first visible sign of someone developing an The word ‘thermometer’ has two roots: meter denotes a device to measure something, and thermo means ‘energy’ or…
Laws and the minus-oneth law of thermodynamics
Feeling the temperature of a radiator is one of the simplest of A ‘law’ in physical chemistry relates to a wide range of situations. experiments. No one has ever sat…
Observed and controlled variables
We want to turn up the radio because it’s noisy outside, and we want to hear what is broadcast. We therefore turn the volume knob toward ‘LOUD’. At its most…
Relationships between variables
The pressure p of the air above any point on the Earth’s surface relates ultimately to the amount of air above it. If we are standing high up, for example…
The Scope Of Chemistry
The days are long past when one person could hope to have a detailed knowledge of all areas of chemistry. Those pursuing their interests into specific areas of chemistry communicate…
What Is Physical Chemistry?
Physical chemistry is the study of how matter behaves on a molecular and atomic level and how chemical reactions occur. Based on their analyses, physical chemists may develop new theories,…
What Is Phosphine?
Phosphine is a chemical which belongs to the group of organophosphorus compounds. This compound was first obtained by Philippe Gengembre in the year 1783. He obtained phosphine by supplying heat…
