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DHS PS CH 19 Part 2
Question | Answer |
---|---|
Why is oxygen written with a subscript 2? | It exists as a diatomic molecule. |
An insoluble compound that comes out of solution during a double displacement reaction is called a? | precipitate |
General formulas represents a single-displacement reaction? | A+BC=>AC+B |
What type of reaction is shown in the following chemical equation: NH3+HCl=>NH4Cl? | synthesis |
The formula AB=>A+B represents what type of chemical reaction? | decomposition |
What type of reaction is represented by the following equation: 2H2+O2=>2H2O? | synthesis |
What type of reaction produces a precipitate? | Double displacement |
In a _____ reaction, two or more substances combine to form another substance. | Synthesis |
Which of the following could represent a decomposition reaction? | Compound --> element + element |
Following equation represents what type of chemical reaction: 2H2(g)+ O2(g)-->2H2O(g)? | synthesis |
A substance that speeds up a chemical reaction without being permanently changed itself is a(n)______. | Catalyst |
Rust forming on a car body would be an example of __ __________ ______________? | a chemical reaction |
Substances that prevent, or slow down, chemical reactions are called ____. | Inhibitors |
Symbols in chemical equation means "produces," "yields", or "forms" | --> |
The burning of wood in a campfire that produces heat and light would be both an ______ and an ______ reaction. | Exergonic, Exothermic |
If heat must be added to a chemical reaction for the reaction to take place, the reaction is ______. | Endothermic |
The energy required to break the original bonds is less than engergy released when new bonds form in a(n) | Exergonic |
In a chemical equation, the symbol that means dissolved in water is ______. | (aq) |
The type of reaction that produces more energy than is required is called _____. | Exergonic |
If heat must be added to a chemical reaction for the reaction to take place, the reaction is _____. | Endothermic |
When one element replaces another element in a compound, the reaction is a _____ reaction. | Single-displacement |
The breaking down of a substance into two or more simpler substances is _____. | Decomposition |
Substances that prevent, or slow down, chemical reactions are called _____. | Inhibitors |
A chemical reaction in which heat energy is released is _____. | Exothermic |
What is an insoluble compound that forms during a chemical reaction? | Precipitate |
A chemical reaction in which two or more substances combine to form another substance is called a _____. | Synthesis reaction |
When most chemical reactions take place, some _____ in the reactants must be broken, a process that requires energy. | Chemical bonds |
The process by which hydrogen and oxygen form water can be classified as a _____. | Synthesis reaction |
TRUE/FALSE: An ice cube melts into liquid water is an example of a chemical reaction. | False |
AB + CD --> AD + CB is an example of a _____ reaction. | Double-displacement |
Why would a catalyst be added to a chemical reaction? | To speed up a reaction |
Some reactions require an input of energy in order to occur. Photosynthesis, the process in which plants use light to make sugars, requires an energy input. This reaction would be classified as _____. | endergonic |
A change in which one or more substances are converted into new substances is called a _____. | chemical reaction |
How would a relationship between reactants and products be shown? | reactants --> products |
What does the law of conservation of mass state? | Matter cannot be created or destroyed, but is conserved. |
The symbol (s)used in a reaction stands for a _____. | solid |
The symbol (l) used in a reaction stands for a _____. | liquid |
The symbol (g) used in a reaction stands for a _____. | gas |
The symbol (aq) used in a reaction stands for _____. | aqueous or dissolved in H2O |
The physical forms in which all matter naturally exists, solid, liquid, and gas, are called _____. | states of matter |
This occurs when a substance reacts with oxygen to produce energy in the form of heat and light. | combustion reaction |
What would be an example of a combustion reaction? | whenever something burns : fireworks, candle, campfire, engine, furnace, grill, etc. |
When hydrogen burns in oxygen to form water, this type of reaction occurs. | synthesis |
TRUE/FALSE: When H2O is broken down into hydrogen and oxygen gases, a decomposition reaction takes place. | true |
Most decomposition reactions require the use of _____, _____, or _____. | heat, light, electricity |
When copper wire is placed in a solution of silver nitrate to produce a copper nitrate sloution and silver on the wire, this is an example of a _____ reaction. | single-displacement |
Why do metals such as copper, silver, and gold exist as pure elements? | They are the least active of the metals on the list. |
A _____ reaction occurs when barium nitrate reacts with potassium sulfate to produce barium sulfate and potassium nitrate. | double-displacement |
What type of reaction produces a precipitate? | double-displacement reaction |
A _____ is the force that holds two atoms together. | chemical bond |
Chemical reactions that release energy are called a(n) __________ reaction. | exergonic |
Chemical reactions that release energy, primarily in the form of thermal energy are _____. | exothermic |
A ______ reaction requires energy. | endergonic |
Chemical reactions that require energy in the form of thermal energy are _____. | endothermic |
A _____ is a substance that speeds up a chemical reaction without being permanently changed itself. | catalyst |
A substance used to slow down a chemical reaction is a(n) _____. | inhibitor |
All chemical reactions ______ or _____ energy. | release, absorb |
What are four examples of energy associated with chemical reactions? | thermal, light, sound, & electricity |
A plastic chair breaking down in the presence of sunlight is an _____ reaction. | endergonic (requires light) |
Logs burning in a campfire would be an example of what type(s) of reaction? | exergonic (produces light and sound), exothermic (produces heat) |
A firefly would be an example of _____. | exergonic (produces light) |
An instant cold pack is an example of what type(s) of reaction? | endothermic |
What type of reaction would a hand warmer pack be? | exothermic |
A change in which one or more substances are converted into a new substance is called a(n) _____ reaction. | chemical |
If a precipitate, water, or a gas forms when two ionic compounds in solution are combined, the reaction is a(n) _____ reaction. | double-displacement |
A substance that prevents certain chemical reactions is a(n) _____. | inhibitor |
When two or more substances combine in a chemcial reaction to form another substance, a(n) _____ reaction has taken place. | synthesis |
The breakdown of a substance into two or more simpler substances is a(n) _____ reaction. | decomposition |
In a chemical equation, the substances that react are called _____. | reactant |
A substance that speeds up a chemical reaction without itself being permanently changed is a(n) _____. | catalyst |
A reaction that requires energy in the form of heat is a(n) _____ reaction. | endothermic |
When one element replaces another in a compound, a(n) _____ reaction has occurred. | single-displacement |
If the energy released in a chemical reaction is primarily in the form of heat, that reaction is a(n) ______ reaction. | exothermic |
An insoluble solid that forms when two ionic compounds in solution are combined is a(n) ______. | precipitate |
The temperature of the beaker holding the reacting substances increased causing a(n) ______ reaction. | exothermic |
The temperature of the beaker holding the reacting substances decreased causing a(n) ______. | endothermic |
Frost formed on the outside of the beaker holding the reacting substances causing a)n) ______. | endothermic |
Name 4 factors that affect reaction rates. | temperature, concentration, volume/pressure, and surface area |
A state in which forward and reverse reactions or processes proceed at equal rates. | equilibrium |
Carbon Dioxide continually escapes and reenters soda is an example of ____________ _______________. | physical equilibrium |
Baking cookies is an example of an ____________ reaction because it requires heat. | endothermic |
The electrolysis of water is an ____________ reaction because it requires electricity. | endergonic |
A chemical reaction inside the abdomen of a firefly produces light is an _______________ reaction. | exergonic |
Coal power plants burn coal to produce energy. This is an example of an ______________ reaction. | exothermic |
All combustion reactions require __________ . | oxygen |
If you increase the temperature of a chemical reaction, the rate of reaction ________________. | increases |
If you increase the concentration of a chemical in a chemical reaction, the rate of reaction ________________. | increases |
If you increase the volume of a chemical reaction, the rate of reaction ________________. | decreases |
If you increase the pressure of a chemical reaction, the rate of reaction ________________. | increases |
If you increase the surface area of a chemical in a chemical reaction, the rate of reaction ________________. | increases |