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Posted inPhysical Chemistry
Covalent bonds and valence
The water molecule always has a composition in which two hydrogen atoms combine with one…
Posted inPhysical Chemistry
Breaking bonds requires an input of energy
A plant accumulates nutrients from the soil as it grows. Such accumulation depletes the amount…
Posted inPhysical Chemistry
Hydrogen bonds
DNA is a natural polymer. It was first isolated in 1869 by Meischer, but its…
Posted inPhysical Chemistry
Elastic and inelastic collisions
In the previous example, we looked at the interactions induced when changing the external pressure,…
Posted inPhysical Chemistry
How is ammonia liquefied?
Compressing ammonia gas under high pressure forces the molecules into close We sometimes call a…
Posted inPhysical Chemistry
The Maxwell–Boltzmann distribution of energies
If no heat was distributed, then our faces and those parts closest to the fire…
Posted inPhysical Chemistry
Motion of particles in the gas phase
The question, ‘What is pressure?’ is another odd question, but is not too difficult to…
Posted inPhysical Chemistry
The ideal-gas equation
A bubble-jet printer is one of the more useful and versatile inventions of the last…
Posted inPhysical Chemistry
The effects of temperature on density
The air around a hot radiator soon acquires heat. We explain this observation from the…
Posted inPhysical Chemistry
‘The material of action so variable’
The classical author Epictetus (ca 50–ca 138 AD) once said, ‘The materials of action are…