Chemical Equations
Signs of a Chemical Reaction
Law of Conservation of Mass
Grab Bag
Elements, Compounds, Mixtures
100
_________________are elements or compounds that are put together in a chemical reaction.
Reactants
100
Leaves change colors in the fall. What is the sign that this is a chemical reaction?
Color Change
100
What law states that matter can’t be created or destroyed?
Law of Conservation of Mass
100
What are pictures B and D a model of?
B-Compound
D-Mixture
100
A ________ is pure substance that contains only one kind of atom.
element
200
________________ are elements or compounds that are made by a chemical reaction.
Products
200
When baking soda and vinegar are mixed bubbles are produced. What is the sign that this is a chemical reaction?
Gas produced
200
Which describes what will happen to atoms in a chemical reaction?
A.Sometimes lost, never rearranged
B.Sometimes lost, gained, or rearranged
C.Never lost or gained, just rearranged
D.Lost or gained, never rearranged
C. Never lost or gained, just rearranged
200
Is lemonade an element, compound or mixture?
Mixture
200
A ______ contains two or more elements and/or compounds that can be physically separated.
mixture
300
Identify the elements and the number of atoms in the following compound:
2H2SO4
2H2SO4
Hydrogen-4 atoms
Sulfur-2 atoms
Oxygen-8 atoms
300
When calcium chloride solution and baking soda solution are mixed a white solid is formed. What is the sign that this is a chemical reaction?
Precipitate
300
The number of atoms in reactants and products must be what?
Equal
300
How many total atoms are in H2O?
3
300
A ________ contains two or more kinds of elements that are chemically combined.
compound
400
6CO2 + 6H2O --> C6H12O6 + 6O2
What are the products.
C6H12O6 + 6O2
400
When a glow stick is bent and the chemical mix. What is the sign that this is a chemical reaction?
Light and/or color change
400
If a chemical reaction such as photosynthesis begins with 6 atoms of carbon (C), how many atoms of carbon (C) should be in the products?
6 atoms of carbon
400
Besides a beaker, give one example of an open system.
test tube, cup, erlenmeyer flask, etc.
400
Element, Compound or Mixture?
Salt (NaCl)
compound
500
6CO2 + 6H2O --> C6H12O6 + 6O2
What are the reactants.
6CO2 + 6H2O
500
Baking a chocolate cake in the oven. What is the sign that this is a chemical reaction?
Strong Odor
500
When baking soda and vinegar are mixed the mass of the reactants is not equal to the mass of the products. What happened to the missing atoms?
The missing atoms escaped as a gas.
500
Besides a sealed bag, give one example of a closed system.
test tube with lid/stopper, cup with lid, bottle with lid, erlenmeyer flask with lid/stopper, etc.
500
What is picture A a model of?
A-Element