Word Power
Reaction ID
It All Adds Up
Chemistry Smarts
Reactive Behavior
100
This is a substance that speeds up a reaction by lowering the activation energy needed to get it started.
What is a catalyst?
100
This would be the balanced reaction
A. 2Zn + HCl → ZnCl2 + H2
B. Zn + HCl → ZnCl2 + H2
C. Zn + 2HCl → ZnCl2 + H2
What is C?
100
What do we call the elements/compounds produced during a chemical reaction that are found to the right of the arrow?
What are products?
100
If water is heated and changes from a liquid to a gas, this type of change-chemical or physical-has occurred.
What is a physical change?
Any change of state/phase (solid to liquid, liquid to gas or solid, etc.) is a physical change.
100
This is a reaction that gives off thermal energy and would feel hot to the touch.
What is an exothermic reaction?
200
This is a substance that slows down or even stops a chemical reaction.
What is an inhibitor?
200
This type of reaction is shown below.
4 Fe + 3 O2 
2 Fe2O3
What is synthesis?
200
What do we call the compounds/elements that are present at the beginning of a chemical reaction and are found to the left of the arrow?
What are reactants?
200
This is a change that can not be easily undone and results in the formation of a new substance. Examples include burning, rusting, rotting, and other reactions.
What is a chemical change?
200
This is a reaction that absorbs thermal energy and would feel cool to the touch.
What is an endothermic reaction?
300
This is the amount of substance that contains 6.02 x 1023 atoms or molecules.
What is a mole?
300
This type of reaction is shown below.
2 HgO 2 Hg + O2
What is decomposition?
300
Balance the chemical equation below.
_____Mg + _____O2 ------> _____ MgO
What is
2Mg + O2 --------> 2MgO ?
300
This change is more easily reversed. It may change the appearance of a substance but does not change its identity. It is still the same substance. Examples include folding paper, breaking glass, or melting a crayon.
What is a physical change?
300
These are signs that a chemical reaction has occurred. (Name at least 3 for full points.)
What are a change of color, a change of temperature, formation of gas/bubbles, release of energy as fire/light/explosion, or the formation of a precipitate?
400
This would be the number of atoms or molecules associated with Avogadro's number.
What is 6.02 x 1023?
400
This type of reaction is shown below.
Cl2 + 2 NaBr 2 NaCl + Br2
What is single replacement?
400
This would be the mass of one mole of H2O.
What is 18 grams?
(1 + 1 + 16)
400
In a chemical reaction or chemical change, chemical bonds ___________ and new chemical bonds ____________.
What is break and form?
400
Describe the effect of each of the following on a chemical reaction:
temperature
concentration
surface area
The higher the temperature, the faster the reaction.
The higher the concentration of the chemicals, the faster the reaction.
The smaller the pieces of a solid (more surface area), the faster the reaction.
500
The amount of energy required to start a chemical reaction is called this.
What is activation energy?
500
This type of reaction is shown below.
Ca(NO3)2 + Na2SO4 2 NaNO3 + CaSO4
What is double replacement?
500
This is the reactant that is used up completely during a reaction.
What is the limiting reactant?
500
This insoluble solid can form in a mixture and drift to the bottom. It's formation can be a signal that a chemical reaction has taken place.
What is a precipitate?
500
This type of nuclear reaction releases energy as more massive nuclei are split into smaller atoms.
What is fission?
600
This principle explains why we must have the same number of atoms of each element type on the left and right of the yield arrow in a balanced equation.
What is the Principle of Conservation of Mass? It states that matter can not be created or destroyed, so the mass should be the same for the reactants and the products.
600
This type of reaction is shown below.
C₃H₈ + 5O₂ → 3CO₂ + 4H₂O
What is combustion?
600
Out of the following processes-combustion, photosynthesis, respiration, and decomposition-this would remove CO2 from the atmosphere.
What is photosynthesis?
600
Imagine that you have a mole of each of these two substances-CO2 and NaCl.
A.) This one would have the greater molar mass.
B.) This one would have the greatest number of molecules.
A. What is NaCl?
B. They would both have the same number of molecules. Remember a mole always contains 6.02 x 1023 molecules/atoms.
600
This type of nuclear reaction releases energy as smaller nuclei combine to form a larger atom.
What is fusion?