Chapter 6
Balance the following chemical equation by filling in the correct coefficients. ____________ KI + BR2 →_____________ KBr + I2.
2 and 2
In the reaction 2H2O2→2H2O + O2 if you start with 4 mol of H2O2 how many moles of O2 will you end up with?
2 mol
In the reaction 2H2O→2H2 + O2, if you start with 2 mol of water, how many moles of hydrogen gas are produced?
2 mol
The changes that are visible during a chemical reaction are signs that the _____________ in the reactants have been rearranged.
atoms
_________________ is an exothermic reaction in which living things produce light.
bioluminescence
When methane burns in the presence of insufficient oxygen, the products of the reaction are water and _____________.
carbon monoxide
A change of color is a sign that a _____________ is taking place
chemical change
Aluminum undergoes a single-displacement reaction with copper (II) sulfate to form aluminum sulfate and _______________.
copper
In a(n)______________ reaction, the reactants are broken down into other substances
decomposition
In a combustion reaction, __________________ is used to make reactants burn.
oxygen
In a chemical reaction, the combined molar masses of the ______________ equal the combined molar masses of the ____________.
reactants and products
In a chemical reaction, atoms are ___________ , but they are not created or destroyed
rearranged
A substance is said to be ____________ when it gains electrons.
redox
If you start with 5 mol of O2 in the reaction 2Mg + O2 →2MgO, how many moles of Mg will you need
10 mol
In the chemical equation H2 + CI2 →2HCI, the mole ratios are ________.
1:2 and 1:2
In the chemical equation FeS + 2HCI → FeCI2 + H2S, the mole ratios are __________________.
1:2 and 2:1
Balance the following chemical equation by filling in the correct coefficient on the right-hand side H2 + CI2 → ______________ HCI.
2
In the chemical equation CH4 + O2 →CO2 + 2H2O, for every one mole of carbon dioxide you produced, you would have ___________ mole(s) of water.
2
You are producing magnesium oxide by the reaction 2Mg + O2 →2MgO. If you start out with 6 moles of Magnesium, you will need __________ moles of oxygen, and you will produce _________ moles of magnesium oxide.
3 and 6
In the reaction H2S + 2O2→H2SO4, the law of definite proportions predicts that for every mol of H2S you will need how many moles of O2?
3 mol
Suppose you were producing zinc chloride by the reaction Zn + 2HCI → ZnCI2 + H2
8 and 4
In the reaction 2Mg + O2 → 2MgO, the law of definite proportions states that for every 2 moles of Mg you will need how many moles of O2
A molar mass of the reactants
A synthesis reaction is a reaction between at least 2 compounds in which
A new, more complex compound is formed
What kind of reaction occurs when potassium is placed in water
A single-displacement reaction
All of the following factors may speed up a chemical reaction except
A smaller surface area
The general formula for a synthesis reaction is __________.
A+B--> AB
What happens in a chemical reaction?
Atoms are rearranged
When methane reacts with abundant amounts of oxygen, the products are
Carbon dioxide and water
A substance that undergoes a change in a chemical reaction is
Chemical
A change in the color of a solution is a sign that
Chemical change is taking place
A chemical equation is balanced by changing or adding
Coefficients
Which of the following is an example of decomposition reaction
Digestion
Which statement about endothermic reactions is correct
Energy is transferred to the reactants
When a chemical reaction and its reverse are occurring at the same time and at the same rate, the reaction has achieved
Equilibrium
Most of the energy in an isooctane reaction is released in the form of
Heat and light
When water is broken down by electrolysis, the products are
Hydrogen and oxygen ions
What is the relationship between chemical equilibrium and the rates of forward and reverse reaction?
In equilibrium the forward and reverse rates must be equal
Increasing the concentration of one substance in an equilibrium reaction favors the reaction that
Involves an enzyme
The energy source in photosynthesis is
Light energy
When iron reacts with oxygen to form rust, each iron atom
Loses 3 electrons
A balanced chemical equation shows the proportions of reactants and products necessary for
Mass to be conserved
A balanced chemical equation indicates both the number of particles of reactants and products and the number of
Moles
Chemical energy is energy that is
Present within atoms and molecules
Fragments of molecules that have at least 1 electron for bonding are called
Radicals
What could you do to make yeast dough rise more slowly
Reduce the heat
In a redox reaction, the substance that excepts electrons is said to be
Reduced
3Le Chatelier's principle states that increasing temperature favors a reaction that
Requires energy as heat
What is the product of synthesis reaction between sodium and chlorine gas is
Sodium chloride
An enzyme is a special kind of catalyst that works to
Speed up a specific biochemical reaction
In an exothermic reaction, energy is transferred from
The reactants to the surroundings
In a balanced chemical reaction, the total mass of the products will always equal the
Total mass of the reactants
Radicals react quickly to form covalent bonds with nearby substances because they have _______________ available for bonding
electrons
The law of definite proportions states that a compound always contains the same _____________ in the same ____________.
elements proportions
A(n) _________________ reaction is one in which heat is transferred from the surroundings to the reactants
endothermic
Photosynthesis is an example of a (n) ___________ chemical reaction in which plants use sunlight to make glucose and oxygen.
endothermic
A chemical reaction that transfers energy from the reactants to surroundings is referred to as ___________.
exothermic
When bread rises, this is a sign that a chemical reaction is producing _____________.
gas
Alkali metals react violently with water to form metal ions, hydroxide ions, and _____________.
hydrogen gas
A catalyst that slows a reaction is called a (n) ____________________.
inhibitor
A sign that a chemical reaction is taking place is release of energy in the form of ___________ or ____________
light or heat
