WorksheetsUNIT 2 Assessment ONLY ONE ATTEMPT
Total questions: 20
Worksheet time: 10mins
The compounds that go into a reaction are called __________, while those that come out are called ________.
products, reactants
elements/equations
reactants/products
atoms/elements
When atoms rearrange to form new substances, a __________________________ has taken place.
Compound Reaction
Physical Reaction
Chemical Reaction
Matter Reaction
Which of the following is NOT a sign of a chemical reaction?
change in phase solid to liquid
precipitate being formed
color change
fizzing
Reactions that absorb thermal energy are
Endothermic
Exothermic
The idea that states the mass of the chemical components before the reaction is equal to the mass of the components after the reaction.
Law of Chemistry
Law of Conservation of Mass
Law of Evolution
Law of Polarity
Which Statement below best describes what it means for an equation to be balanced?
The number of molecules is the same before and after the reaction occurs.
There are the same number of atoms on the reactant side and the product side of the equation.
The coefficients are equal to the subscripts.
The only way to know for sure if a chemical reaction took place is to test the properties of the new substance.
True
False
When balancing a chemical equation, you are allowed to change the subscripts.
True
False
When balancing a chemical equation, you are allowed to change the coefficients.
True
False
How many glucose molecules are there in the figure?
2
4
8
12
How many atoms of Hydrogen are there in the figure?
4
6
12
24
Determine if the following equation follows the law of conservation of mass. (Are they balanced?).
N₂ + H₂ → NH₃
Y
N
Determine if the following equation follows the law of conservation of mass. (Are they balanced?).
See #13 on Test Sheet
Y
N
Determine if the following equation follows the law of conservation of mass. (Are they balanced?).
P + O₂ → P₂O₅
Yes
No
Determine if the following equation follows the law of conservation of mass. (Are they balanced?).
SEE #15 on TEST SHEET
Yes
No
Determine if the following equation follows the law of conservation of mass. (Are they balanced?).
2 H₂ + O₂ → 2 H₂O
Y
N
Determine if the following equation follows the law of conservation of mass. (Are they balanced?).
SEE #17 on Test Sheet
Y
N
If 46.5 grams of reactants are used in a reaction, what will be the mass of the products? (Fill in the Answer)
(a)
A chemical reaction produces two new substances: 72 grams of water and 64 grams of oxygen. What was the total mass of the reactant(s)?
(a)
Use TABLE from Test Sheet Question #20:
A student makes some observations about three solids and summarizes the results in the table.
Could any of the solids be the same substance and why?
Solids 1 and 2 could be the same substance. Even though they do not have the same melting point, they have the same mass.
Solids 2 and 3 could be the same substance. Even though they do not have the same mass, they have the same melting point and color.
Solids 1, 2 and 3 could all be the same substance. Even though they do not have the same mass and melting point, they have the same color.
Solids 1, 2 and 3 cannot be the same substance because they have different combinations of color, melting point, and mass.
