Element, Compound, or Mixture?
H2O (water)
Compound
How many atoms of each element, and how many total atoms are in caffeine?
C8H10N4O
Carbon- 8
Hydrogen- 10
Nitrogen- 4
Oxygen- 1
Total- 23
Solid, Liquid, or Gas:
The phase with the most kinetic energy, particles spread out to fill the container.
Gas
List the reactants and products:
Zn + 2 HCl → H2 + ZnCl2
Reactants: Zn + 2 HCl
Products: H2 + ZnCl2
Give an example of a physical change
Answers will vary
N2 (nitrogen gas)
Element
How many atoms of each element, and how many total atoms are in Fool's Gold?
FeS2
Iron- 1
Sulfur- 2
Total- 3
Solid, Liquid, or Gas:
The phase with the least kinetic energy, particles are packed together tightly and can only vibrate in place.
Solid
According to the Law of Conservation of Matter, the mass of the products must ________ the mass of the reactants.
a) be less than
b) be greater than
c) equal
Equal
Give an example of a chemical change
Answers will vary
Milk
Mixture
How many atoms of each element, and how many total atoms are in table salt?
NaCl
Sodium- 1
Chlorine- 1
Total- 2
Solid, Liquid, or Gas:
In this phase particles can flow or slide past each other, its shape depends on the container it is in.
Liquid
MgO + CO2 --> MgCO3
24g + 32g --> ?
56 g
What are 2 ways you could know if a chemical change occured? (evidence)
Production of a gas/bubbles, color change, temperature change, production of light, formation of a precipitate.
C8H10N4O (caffeine)
Compound
How many atoms of each element, and how many total atoms are in glucose?
C6H12O6
Carbon- 6
Hydrogen- 12
Oxygen- 6
In these phase changes, molecules lose energy and slow down (3 answers required)
Freezing, Condensation, and Deposition
Mrs. Thomas put 1.5 kg of ice into a closed jar. When it melts into water, how much will be in the jar?
1.5 kg
What is one physical change and one chemical change that occurs in the process of making a pizza.
Physical: slicing the pizza, shredding the cheese, etc.
Chemical: cooking the pizza, crust turns brown, etc.
Kool-Aid (powdered drink mix in water)
Mixture
How many atoms of each element, and how many total atoms are in methane (cow farts)?
CH4
Carbon- 1
Hydrogen- 4
Total- 5
In these phase changes, molecules gain energy and speed up (3 answers required)
Melting, Vaporization, Sublimation
If there are 20 atoms of hydrogen in the reactants, how many atoms of hydrogen will there be in the products?
20
Physical or Chemical:
Ice melts into water, water evaporates into vapor.
Physical