Phase Change
At room temperature, mercury is a liquid. However, when heated to 356.73 °C, mercury forms a gas that is toxic if inhaled. What type of phase change process is represented?
Evaporation
Which of the following is the strongest type of intermolecular force?
Hydrogen Bonding (it's FON)
What are units of Temperature scientist use?
Daily Double if you can write the equations
Kelvin & Celsius
Daily Double: Which intramolecular bond(s) is missing and describe it?
Polar molecules: 1) Have at least one polar bond. 2) Is not symmetrical 3) Oppositely charged ends
Non-Polar molecules: 1) Has non-polar bonds 2) Is symmetrical 3) Similarly charged ends
Ionic Bonds = metal + nonmetal
Metallic = metal + metal
Write the name of this element?
C3N4
Tricarbon Tetranitride
Carbon: Melting Point: 3500 C Boiling Point: 4827 C
Using the chart above to the top right, what phase change occurs when carbons temperature is decreased from 5000 to 4000 degrees? Why?
What is Condensation?
when a vapor goes to a liquid = Condensation.
The initial phase is a gas because the initial temperature is above the Boiling Point (BP). The final phase is a liquid because final temperature is below the BP but higher than the Melting Point (MP)
Which of the following molecules exhibits a dipole-dipole interaction?
The temperature at which all molecular motion stops is:
a) -460 o C b) -273 o K c) 0o K d) -0o C
Daily Double 2X if you get vocabulary
Absolute Zero is when all motion stops
0o K, -273 o C, 459.4o F
Polar Covalent Bond leads to which type of intermolecular bonds?
Dipole- Dipole Interactions
Which is the correct formula for the compound chromium (II) oxide?
a) Cr2O3 b) CrO c) CrO3 d) CrO2
Cr2+ O2- Charges
Cr2O2 Molecular
CrO- Empirical
Humidity in the air (water vapor) from a shower transformed into water droplets (liquid) on the mirror. What type of phase change process is represented?
Condensation
What happens to the boiling point of water when the altitude is increased?
Boiling point increases because there is more pressure
Boiling point increases because there is less pressure
Boiling point decreases because there is more pressure
Boiling point decreases because there is less pressure
Boiling point decreases because there is less pressure
Increase in Altitude -->Decrease Pressure atmospheric pressure -->Decrease Boiling Point
If a compound only has London Dispersion then the intramolecular bonding present is:
a) Ionic b) Polar Covalent c) Non Polar
Non - Polar
What is the formula for diphosphorous trioxide?
a. F2O b. PO3 c. P2O6 d. P2O3
What were charges of elements initially?
P2O3
Sometimes substances can skip the liquid phase and go directly from a solid to a gas or directly from a gas to a solid. Which of these phase changes occur when energy is added (increased)?
Solid to gas, called sublimation
CCl4
Carbon Tetrachloride
Which of the following statements most accurately describes surface tension?
a. As the temperature of the water increases, the surface tension increases.
b. As the temperature of the water increases, the surface tension stays the same.
c. As the temperature of the water increases, the surface tension decreases.
d. As the strength of intermolecular attraction between water molecules increases, the surface tension decreases.
c. As the temperature of the water increases, the surface tension decreases.
(Water into Ice example)
Nonpolar Molecules display which type of intermolecular forces?
Van der Waals, London Dispersion or induced dipole dipole
If Cu+ is a stable ion, which ionic compounds is iron most likely to form with oxygen (O2-)?
a) Cu2O2 b) CuO c)CuO2 d)Cu2O
Write full chemical formula:
Daily Double
Cu2O
Copper (I) Oxide
Sometimes substances can skip the liquid phase and go directly from a gas to a solid or directly from a gas to a solid. Which of these phase changes occur when energy is removed (decreased)?
Gas to solid, called deposition
Cl2 has a lower boiling point than HCl. Why would Cl2 have a lower boiling point?
Cl2 is non-polar --> Induced Dipole Dipole --> Weaker Intermolecular Forces --> Lower Boiling & Melting Points
HCl is polar --> Dipole-Dipole --> Higher Boiling & Melting Points
When pressure does not change what would happen with a temperature increase?
Water displays which type of Intermolecular forces?
Why does it display this type of intramolecular bonds?
Daily Double
Hydrogen Bonding is the intermolecular forces displayed due to polar molecules that have a highly electronegative element with strong nuclear force (FON) attach to H sharing electrons with other molecules as a result.
Explain answer for daily double
tin (IV) chloride