4.1 States of Matter Flashcards
Describe kinetic theory.
Kinetic theory says that all matter is made from particles that are constantly in motion.
Describe the behaviour of water according to kinetic theory.
The particles in water have more kinetic energy than those in a solid which weakens the intermolecular forces holding them together. This allows the particles to move around each other freely.
Describe the behaviour of gas according to kinetic theory.
The intermolecular bonds in a gas are so weak that the particles can move independent to one another. This is because particles in a gas have such high kinetic energy that the bonds cannot hold them togther.
Describe the behaviour of solids according to kinetic theory.
Particles in a solid have the least kinetic energy and so intermolecular bonds are able to hold them in a lattice.
Describe brownian motion.
The random motion of a particle as a result of collisions with another particle.
Describe a thermistor thermometer.
Thermistor thermometers (such as the ones used for clinical purposes) use a thermistor (a resistor whose resistance depends on temperature). The resistance is measured and converted to temperature.
Describe a thermocouple thermometer.
These use a set of paralell wires that are made from different metals. There are two junctions where these wires meet, one is a cold junction, and a hot junction. When the ambient termperature rises, a current is produced and converted to a temperature.
What is absolute zero in degrees C?
-273C
Describe thermal expansion.
Thermal expansion occurs when a substance is heated. Its particles gain kinetic energy and therefore take up more space because of their increased vibrations. This causes the overall volume of the substance to increase.
What happens when a gas is heated.
A gasses volume depends on the container it is in, so only at a fixed volume does pressure increase with temperature
