WorksheetsChemical Reactions Test
Total questions: 30
Worksheet time: 42mins
Chemical reactions ____.
occur only in living organisms
create and destroy atoms
only occur outside living organisms
produce new substances
Identify the letter of the choice that best completes the statement or answers the question. 2. Everyday equations describe ____.
thermonuclear reactions
everyday processes
chemical reactions
biological chemistry
What does the symbol Δ in a chemical equation mean?
Heat is supplied to the reaction.
A catalyst is needed.
yields
precipitate
Chemical equations ____.
describe chemical reactions
show how to write chemical formulas
give directions for naming chemical compounds
describe only biological changes
A skeleton equation does NOT show which of the following?
the correct formulas of the reactants and products
the reactants on the left, the products on the right
an arrow connecting the reactants to the products
the relative amounts of reactants and products
Which set is correct?
(g), grams
(l), liters
(aq), dissolved in water
(s), solid product
A catalyst is ____.
the product of a combustion reaction
not used up in a reaction
one of the reactants in single-replacement reactions
a solid product of a reaction
Which of the following is the correct skeleton equation for the reaction that takes place when solid phosphorus combines with oxygen gas to form diphosphorus pentoxide?
P(s) + O2(g) → PO2(g)
P(s) + O(g) → P3O5(g)
P(s) + O2(g) → P2O5(s)
P2O5(s) → P2(s) + O2(g)
When the equation Fe + Cl2 → FeCl3 is balanced, what is the coefficient for Cl2?
1
2
3
4
Which of the following statements is NOT true about what happens in all chemical reactions?
The ways in which atoms are joined together are changed.
New atoms are formed as products.
The starting substances are called reactants.
The bonds of the reactants are broken and new bonds of the products are formed.
Chemical equations must be balanced to satisfy ____.
the law of definite proportions
the law of multiple proportions
the law of conservation of mass
Avogadro's principle
In every balanced chemical equation, each side of the equation has the same number of .
molecules
moles
coefficients
In order to predict whether or not a single-replacement reaction takes place, you need to consult a chart that shows the .
periodic table
common polyatomic ions
ionic charges of representative elements
In a combustion reaction, one of the reactants is .
hydrogen
nitrogen
a metal
The products of a combustion reaction do NOT include .
carbon dioxide
carbon monoxide
hydrogen
Which of the following statements is NOT correct?
The only way to determine the products of a reaction is to carry out the reaction.
All chemical reactions can be classified as one of five general types.
Complete combustion has occurred when all the carbon in the product is in the form of carbon dioxide.
A single reactant is the identifying characteristic of a decomposition reaction.
Which of the following statements is NOT true about the decomposition of a simple binary compound?
The products are unpredictable.
The products are the constituent elements.
The reactant is a single substance.
The reactant could be an ionic or a molecular compound.
Which of the following statements is true about single-replacement reactions?
They are restricted to metals.
They involve a single product.
Two reactants produce two products.
Any metal replaces any other metal.
In the activity series of metals, which metal(s) will displace hydrogen from an acid?
only metals above hydrogen
only metals below hydrogen
any metal
only metals from Li to Na
Which of the following statements is NOT true about double-replacement reactions?
The product may precipitate from solution.
The product may be a gas.
The product may be a molecular compound.
The reactant may be a solid metal.
What is the driving force in the following reaction? Ni(NO₃)₂(aq) + K₂S(aq) → NiS(s) + 2KNO₃(aq)
A gas is formed.
A precipitate is formed.
Ionic compounds are reactants.
Ionic compounds are products.
Which of the following is a characteristic of a combustion reaction?
It involves the exchange of ions between two compounds.
It always produces carbon dioxide and water.
It requires a catalyst to proceed.
It occurs only in the presence of a metal.
What is the role of a catalyst in a chemical reaction?
It changes the products of the reaction.
It lowers the activation energy of the reaction.
It is consumed during the reaction.
It increases the temperature of the reaction.
In a balanced chemical equation, the number of atoms of each element is ____.
greater on the product side
not important
equal on both sides
greater on the reactant side
In this chemical equation, the elements in red are the_______.
Products
Reactants
Subscripts
Coefficients
Which of the following is a characteristic of a decomposition reaction?
It always produces water and carbon dioxide.
It involves the combination of two or more substances.
It requires a catalyst to proceed.
It results in the breakdown of a compound into simpler substances.
What is the role of heat in a chemical reaction?
It increases the rate of the reaction by providing energy.
It acts as a reactant.
It is a product of all chemical reactions.
It is always required for a reaction to occur.
Which of the following statements is true about the law of conservation of mass?
Mass is neither created nor destroyed in a chemical reaction.
Mass is destroyed during a chemical reaction.
Mass is created during a chemical reaction.
Mass is only conserved in physical changes.
