Phase Changes
Density
Physical or Chemical?
Chemical Equations
Types of Reactions
100
Describe particle motion in a gas.
Particles have a lot of energy and move freely.
100
Which of these are more dense?
The square on the left.
100
Physical or chemical:
Water freezing
Physical
100
Balance this equation:
H2 + O2 --> H2O
Daily Double
2H2 + O2 + 2H20
100
What is a synthesis reaction?
A reaction where two different elements or compounds combine to form a single, more complex substance.
200
What are the 4 main phases of matter?
Solid, liquid, gas, plasma
200
Define density in your own words.
How much mass is held in a certain volume of a substance OR how many particles are in a certain amount of a substance.
200
Physical or chemical: Rust
Explain how you know.
Rust is a chemical change because it is irreversible and changes the composition of the substance from iron to iron oxide.
200
Balance this equation:
N2 + H2 --> NH3
N2 + 3H2 --> 2NH3
200
What is a decomposition reaction?
A reaction where one compound splits apart into two or more substances (elements or simpler compounds).
300
What is an example of a plasma?
Daily Double
Lightning, Fire
300
Find the mass:
Calculate the mass of a liquid with a density of 2.5 g/mL and a volume of 15 mL
37.5g
300
Give an example of a chemical property. Explain why it is chemical.
Answers vary.
300
In your own words, what is the Law of Conservation of Mass?
"Matter is neither created nor destroyed."
300
What kind of reaction is this?
Zn + HCl -> ZnCl2 + H
Single replacement
400
Explain in your own words: What are condensation & vaporization?
Give an example of either.
Condensation: Going from a gas to a liquid (Ex: water on the outside of a cold glass)
Vaporization: Going from a liquid to a gas (Ex: evaporation)
400
Solve the density equation:
A chef fills a 50 mL container with 43.5 g of cooking oil. What is the density of the oil?
0.87g/mL
400
Explain why density and state of matter can be considered physical properties.
You do not have to change the substance to observe density or state of matter. Also, a phase change does not create a new substance.
400
Balance this equation:
GaF3 + Cs --> CsF + Ga
Bonus 100pt: What kind of reaction is this?
GaF3 + 3Cs --> 3CsF + Ga
Bonus: Single Replacement
400
What kind of reaction is this?
CH4 + O2 --> H2O + CO2
Daily Double
Combustion reaction
500
Explain in your own words: What are sublimation & deposition?
Give an example of either.
Sublimation: Changing from a solid to a gas (Ex: Dry ice)
Deposition: Changing from a gas to a solid (Ex: Frost on a windshield)
500
Solve the density equation:
A solid magnesium flare has a mass of 1300g and a volume of 743 cm3. What is the density of magnesium?
1.8g/cm3
500
What are 3 examples of evidence of a chemical change?
1. Gas production
2. Change in odor
3. Unexpected color change
4. Release of energy (light, heat, sound, etc.)
5. Precipitate formation
500
Balance this equation:
CF4 + Br2 --> CBr4 + F2
CF4 + 2Br2 --> CBr4 + 2F2
500
What is the difference between an Endothermic and an Exothermic reaction?
Exothermic: Energy is released
Endothermic: Energy is absorbed