Light and whatnot
___ reflects light and ___ absorbs light.
White; black
___ is the use of energy to move atoms and molecules in a nonrandom or orderly motion.
Work
What is Boyle's Law?
If the pressure on a gas sample is increased at constant temperature, its volume will decrease (P1V1 = P2V2).
Frequency and wavelength have a ___ kind of relationship.
Inverse
C3H8+O2→CO2+H2O
C3H8+5O2→3CO2+4H2O
___ is when an excited electron returns to its original orbit, producing heat or light.
Electron relaxation
Energy can neither be created nor destroyed, only transferred.
What is the First Law of Thermodynamics?
What significant phenomenon occurs in the mesosphere?
Falling stars and the aurora borealis.
What is the impact of ozone depletion on crops and marine ecosystems?
It damages them due to increased UV-B exposure.
Convert 394 Joules to Calories
94.16826 Calories
___ is what makes leaves green and ___ is what makes them turn orange.
Chlorophyll; carotenes
What is the enthalpy of combustion (ΔHcom)?
The enthalpy of reaction for a combustion (burning) reaction.
What is Charles's Law?
If the temperature of a gas is increased at constant pressure, its volume will increase in direct proportion.
Consider the molecule SF₂.
Draw or describe its Lewis structure.
What is the electron geometry around sulfur?
What is the molecular shape?
Is SF₂ overall polar or nonpolar?
Lewis structure:
Sulfur in the center, single‑bonded to two F atoms.
Sulfur has 2 lone pairs; each F has 3 lone pairs.
Total: 6 valence e⁻ from S + 7×2 from F = 20 e⁻, all accounted for.
Electron geometry:
Four electron domains (2 bonds + 2 lone pairs) → tetrahedral electron geometry.
Molecular shape:
With 2 bonds + 2 lone pairs → bent (like H₂O).
Polarity:
The S–F bonds are polar and the bent shape means dipoles don’t cancel → SF₂ is polar.
Convert 78K to F
K = °C + 273.
°C = 5/9 [ °F − 32].
-319.27 F
What type of light contains only one wavelength and is aligned or in phase?
Laser light
Kinetic energy is energy of motion; potential is the energy of position.
What is the Combined Gas Law?
It combines Boyle's law and Charles's law to determine the effects of changes in pressure, temperature, and volume simultaneously.
FALSE
A gas has a volume of 3.6 L at a pressure of 1.2 atm. If the pressure increases to 2.4 atm, what is the new volume (temperature constant)?
1.8 L
Acronym for laser
Light Amplification by Stimulated Emission of Radiation
For any process to be spontaneous, energy must be dispersed, and the entropy of the universe must increase.
What is the Second Law of Thermodynamics?
N2
What are chlorofluorocarbons (CFCs) used for?
Refrigeration, air-conditioning, and as propellants.
When 12.0 g of hydrogen gas (H₂) reacts with excess oxygen, how many grams of water are produced?
108 g of H₂O
1. Convert grams of H₂ to moles
Molar mass of H₂ = 2.0 g/mol
moles H2=12.02.0=6.0 mol
2. Use mole ratio
From the balanced equation:
2H2→2H2O
So the ratio is 1 : 1
6.0 mol H2→6.0 mol H2O
3. Convert moles of H₂O to grams
Molar mass of H₂O = 18.0 g/mol
6.0×18.0=108 g