CEM 141 Chapter 1
Matter - ANS-- Made up of atoms
Atoms - ANS-- Smallest distinguishable part of an element.
We use models (mental and physical) - ANS-to represent many chemical entities
We use different models - ANS-for different purposes
Theories (such as atomic theory) - ANS-change over time according to the evidence available.
All atoms and molecules attract each other - ANS-because of the attractive electrical forces
between them
Attractions - ANS-lower the potential energy of the system
Repulsions - ANS-tend to raise the potential energy
Stable systems form - ANS-where the attractive forces and the repulsive forces are equal
The temperature of a phase change depends on - ANS-the strength of the intermolecular forces
Discovery of the electron - ANS-JJ Thomson
Cathode ray tube - ANS-glass tube consisting of two electrodes under very low pressure, when
high voltage is applied, cathode emits particles that move toward anode
The type of the metal that the cathode was made of - ANS-didn't affect the behavior of the ray
Observations from Thompson's Experiment - ANS-- "Particles" emerged from one disc (the
cathode) and moved to other (the anode)
- These particles could be deflected by electrical fields in a direction that would indicate they
were negatively charged
* (The particles could be deflected by magnetic fields)
* The particles carried the electrical charge - that is if the ray was bent, for example by a
magnetic field, the charge went with it
- The metal that the cathode was made of did not affect the behavior of the ray - so whatever
the composition of the ray - it appeared to be independent of the element that it came from.
Matter - ANS-- Made up of atoms
Atoms - ANS-- Smallest distinguishable part of an element.
We use models (mental and physical) - ANS-to represent many chemical entities
We use different models - ANS-for different purposes
Theories (such as atomic theory) - ANS-change over time according to the evidence available.
All atoms and molecules attract each other - ANS-because of the attractive electrical forces
between them
Attractions - ANS-lower the potential energy of the system
Repulsions - ANS-tend to raise the potential energy
Stable systems form - ANS-where the attractive forces and the repulsive forces are equal
The temperature of a phase change depends on - ANS-the strength of the intermolecular forces
Discovery of the electron - ANS-JJ Thomson
Cathode ray tube - ANS-glass tube consisting of two electrodes under very low pressure, when
high voltage is applied, cathode emits particles that move toward anode
The type of the metal that the cathode was made of - ANS-didn't affect the behavior of the ray
Observations from Thompson's Experiment - ANS-- "Particles" emerged from one disc (the
cathode) and moved to other (the anode)
- These particles could be deflected by electrical fields in a direction that would indicate they
were negatively charged
* (The particles could be deflected by magnetic fields)
* The particles carried the electrical charge - that is if the ray was bent, for example by a
magnetic field, the charge went with it
- The metal that the cathode was made of did not affect the behavior of the ray - so whatever
the composition of the ray - it appeared to be independent of the element that it came from.
