CHEMISTRY
What is Entropy?
The measurement of disorder (chaos) in a system.
How does Entropy change when something changes from its natural state?
The Entropy(s) will increase when something changes from a natural state because the particles are out of their natural order.
Give an example of work being done BY a gas.
steam expanding inside a steam engine
How would the rate of diffusion differ for substances in liquid (water) versus substances in a gas (oxygen)?
The rate of diffusion would be slower for substances that are liquid compared to substances that are gas because particles move faster.
Describe how the energy transfer occurs in our calorimeter experiment with the metal cube. When did it stop?
The energy of the metal cube was transferred to the water when it was put in the calorimeter. This stopped at thermal equilibrium. (cube = water) ---> 1st law of thermodynamics
A chemical reaction occurs in a flask with an attached syringe. The reaction ABSORBS (+) 135 joules (J) of energy and DOES (-) 28 J of work on the syringe. Calculate the change in energy in joules of the system.
Q+W=ΔU
+135J + -28J=107J
If two substances are sitting at the same temperature and pressure (STP), but have different average speeds, why could this be the case?
Two different molar masses
Draw a graph representing the relationship between temperature and pressure. Give 1 real-world example.
pr l /
es l / EX: Hot air balloon
su l /
re l /
l/__________________________
Temperature
Draw a graph representing the relationship between volume and pressure. Give 1 real-world example.
P l .
R l . EX: opening soda bottle
E l .
S l .
S l .
U l .
R l .
E l .
l .
l .
l .
.l___________________________ .
Volume
Draw a graph representing the relationship between temperature and volume. Give one real-world example.
V l /
O l /
L l / EX: Car Tires
U l /
M l /
E l /
l/__________________________
Temperature
S waves cannot travel through outer core because it is composed of ______ ; Refrected P-waves can be recorded where they aren't expected to be because they can travel through _____ & _____ & ______
liquid ; solid & liquid & gas
Give an example of material for each phase change
a. Melting / b. Freezing / c. Evaporation / d. Condensation / e. Sublimation / f. Deposition
a. ice ---> water (liquid) / b. popsicles from juices / c. Shower Steam / d. drops of dew / e. dry ice / f. frost or soot.
What is the composition of earths layer : inner core, outer core, D+E
Solid, liquid, S-wave pattern, P-wave pattern
The triple point of a phase diagram is the point at which _____ _____ phases exist. This point can be found at the ______ of the diagram.
all 3; fork
An unknown substance requires 296 J of energy in order to increase its temperature from 27 °C to 105 °C. You are working with 3.95g of this substance. What is the specific heat capacity of this unknown substance?
c= 296J / (3.95g)(78°C) = 296/308.1 = 0.96
A phase diagram represents where phases exist in ______
equilibrium
What is the second law of thermodynamics?
All real processes increase entropy of the universe
What is the order of layers from TOP to BOTTOM on the Earth? How does energy flow in the earth (draw an arrow)
Top: CRUST /\
MANTLE l
OUTER CORE l
Bottom: INNER CORE l
At what boundaries does ridge push occur and what can usually be found at these locations?
Ridge push occurs at divergent boundaries and causes mid-ocean ridges.
At what boundaries does slab pull occur and what can usually be found at these locations?
Slab pull occurs at convergent boundaries and causes deep-sea trenches.
Low entropy means you have _____ order ; An example of a low entropy system could be ____________________________________
High ; audience in a movie theater
students storming a field after a win.
Which state of matter has the highest matter of entropy? Why?
The state that has the highest amount of entropy is gas because they move the fastest and are all dispersed all throughout, which means they have the highest amount of energy.
What are ALL the variables that can be used to determine the state of a gaseous system?
Pressure (P)
Volume (V)
Number of Moles/Particles (N)
Temperature (T)
Yah
No