What is the measurement of kinetic energy called?
All phase changes (changing states) require some amount of energy to be added or taken away.
In our Amplify story, the liquid methane lake...
When the liquid methane lake evaporated...
the kinetic energy increased and the molecules moved further apart.
the kinetic energy decreased and the molecules moved further apart.
the kinetic energy increased and the phase changed to solid methane.
the kinetic energy decreased and the phase change that occurred was melting.
In our Amplify story, the methane lake did not evaporate right away because...
evaporation of any liquid always takes a long time to occur.
the kinetic energy from the Sun quickly overcame the molecular attraction in the methane.
the methane has high molecular attraction, so it took a lot of energy from the Sun over several years to overcome the attraction.
the lake was in winter up until 2007, so it could not get enough energy from the Sun to vaporize.
Which two factors affect whether or not a phase change happens?
Kinetic Energy and Temperature
Molecular Attraction and Kinetic Energy
Type of molecule and type of container
Season and Location
Which is the best definition of "molecular attraction"?
Molecules that get close together and bond to make a new molecule.
The pull between molecules that is always the same for a substance.
The way that all molecules in a solid have the same pull or attraction, no matter what the substance is made of.
How fast or quickly molecules move in a substance.
Consider oxygen gas. If the molecular attraction of oxygen overcomes the kinetic energy, the oxygen will…
remain as a gas.
condense into a liquid.
vaporize into a liquid.
melt into a liquid.
Consider liquid water. If the kinetic energy overcomes the molecular attraction of water, it will…
remain as a liquid.
freeze into a solid.
evaporate into a gas.
condense into a liquid.
There is a safe chemical and a toxic chemical, and both are liquids at room temperature. When the same amount of energy is transferred out of the two chemicals, only the toxic chemical changes phase. How is the toxic chemical different from the safe chemical?
The toxic chemical has a . . .
weaker attraction between its molecules than the safe chemical. Its molecules now move in place.
stronger attraction between its molecules than the safe chemical. Its molecules now move away from each other.
stronger attraction between its molecules than the safe chemical. Its molecules now move in place.
There are two liquid substances, substance A and substance B. The same amount of energy is transferred into both substances and the temperature is raised. Substance A remained a liquid while Substance B vaporized into a gas. We can tell that…
substance B has less molecular attraction than substance A.
substance A has less molecular attraction than substance B.
these substances are both made of the same molecules.
substance A must be methane and substance B must be water.