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WorksheetsChemical reactants Post
Total questions: 28
Worksheet time: 40mins
A burning candle wick is an example of _________________________
physical reaction
condensation
neutrons
chemical reaction
The starting materials in a chemical reaction
Products
Reactants
Initiators
Finalizers
The substances listed on the right side of a chemical equation are
Yield
Reactants
Products
Precipitates
The process by which one or more substances change to produce one or more different substances
Chemical Process
Reagent
Chemical Reaction
In the equation, 2Mg + O2 ---> 2MgO, what are the reactants?
Mg and O
MgO
Mg and MgO
O and MgO
What are chemical reactions?
It's when you mix substances.
A process in which atoms are rearranged to form new substances.
When something bubbles.
Letters and numbers that show the types and quantity of atoms.
A different chemical substance is formed when _____.
water boils
metal rusts
ice melts
rock is crushed
Identify the following process: We light a match.
Physical change
Chemical change
Chemicals that help to initiate or accelerate a reaction...
Reactants
Products
Catalysts
True or False
In a chemical reaction, no new atoms are created and no atoms are destroyed.
true
false
The left side of the equation below is called
Products
Reactants
A number in front of a chemical formula in an equation that indicates how many molecules or atoms of each reactant and product are involved in a reaction.
Coefficient
Reactant
Subscript
Product
The Law of Conservation of Energy states:
Energy can be created or destroyed but not transformed
Energy cannot be created or destroyed, only transformed
Energy cannot be created, destroyed, or transformed
This term refers to the amount of matter contained in an object.
Joules
Matter
Energy
Mass
Energy cannot be destroyed.
True
False
Energy can be created.
True
False
In a ___________ change, a substance is transformed into a different substance.
Physical
Chemical
Which of these is NOT a sign that a chemical change has occurred?
A loss of transparency
An unexpected color change
A temperature change
The formation of a precipitate
In a chemical reaction, bonds are broken and new bonds are formed to create new substances. What are the bonds that are broken called?
Reactants
Products
Atoms
Catalysts
The Law of Conservation of Mass states
that matter exists in all states and reacts in the same way
that matter can only be transformed into new substances by introducing a catalyst
that matter exists in the same state during any chemical change
that matter cannot be created or destroyed and that the mass of the products must be equal to the mass of the reactants
If the reaction starts with 20g of reactants, it should produce
a total of 40g of products
a total of 10g of products
a total of 80g of products
a total of 20g of products
Which of the models of a chemical reaction best represents the Law of Conservation of Mass?
A
B
C
D
When a chemical reaction occurs...
New molecules and atoms are formed
Molecules and atoms are rearranged
Molecules and atoms disappear
Molecules and atoms are destroyed
What is a chemical equation?
chemical formulas and symbols are written to represent a reaction
a chemical equation is an equation with chemicals combined into a single chemical
chemical equations represent the conservation of mass in a chemical reaction
a dog that ate chemicals
Combining substances to form new substances is called
Chemical reaction
Physical reaction
Exothermic reaction
Endothermic reaction
Matter cannot be created or destroyed: it can only be
Destroy a little
Invisible
Transform, change
None of the above
What are the reactants in this chemical equation?
6 CO2 + 6 H2O
H2O
C6H12O6
C6H12O6 + O2
A substance is heated and is bubbling. However, upon heating, a precipitate formed and it changed color. Did a chemical reaction occur? Use claim, evidence, and reasoning to support your answer.
