Shaun Williams, PhD Professor of Chemistry
Matter and Energy
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Matter: anything that occupies space and has mass.
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- Matter is composed of atoms
- Atom is the name we give to the smallest unit of an element that retains the chemical properties of that element
- Matter is composed of atoms
Physical Properties of Matter
- are properties that can be observed without changing the composition of the substance
Four common physical properties are:
- mass
- volume
- density
- temperature
However, as we shall see, density is the relationship of mass to volume. So why do we need the last two? Surely it would be enough to speak of the density of the matter in hand, and then divide it up into mass and volume, which are like brother and sister. Because the one measures the "dense enough to be 'measured/perceived', and the other the space that the matter with a particular mass occupies. If it is dense, there will be not much space, and if it is gaseous, there will be much more space.
Finally, I ask the question whether temperature is an innate characteristic of the matter in question, or whether it is just a measure of deviance? And if energy is the capacity to transfer heat, is not the temperature of the item a measure of the heat that it is containing, or, perhaps, the energy that one has "absorbed".
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Energy
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What is Energy?
Energy is the capacity to do work or to transfer heat
Two main forms of energy are:
- Kinetic energy: the energy of motion
- Potential energy: energy possessed by an object because of its position
{ NOTE: Mass as energy at "rest", or in a stasis. This "mass event" can possibly contain excess energy, which will be express by the transfer of energy by or from the mass. }
Units for energy are calories or joules
- A calorie is the amount of energy required to raise 1g of water by 1oC