The Nature of Chemical Reactions
Reaction Types
Balancing Chemical Equations
Rates of Change
Random
100
A substance that undergoes a change in a chemical reaction is...
What is reactant
100
A synthesis reaction is a reaction between at least two compounds in which
What is a new, more complex compound is formed.
100
A chemical equation is balanced by changing or adding...
What is coefficients.
100
What could you do to make yeast dough rise more slowly?
What is Reduce the temperature.
100
What happens in a chemical reaction?
What is Atoms are rearranged.
200
Chemical energy is energy that is...
What is present within atoms and molecules
200
When water is broken down by electrolysis, the products are...
What is hydrogen gas and oxygen gas...
200
In a balanced chemical reaction, the total mass of the products always equals the...
What is total mass of the reactants.
200
When a chemical reaction and its reverse reaction are occurring at the same rate, the reaction has achieved...
What is equilibrium.
200
What kind of reaction is digestion?
What is decomposition.
300
A chemical reaction that transfers energy from the reactants to the surroundings is referred to as...
What is exothermic
300
A substance is said to be_________when it gains electrons.
What is reduced.
300
Balance the following chemical equations by filling in the correct coefficient on the right-hand side. H2 + Cl2 -->__HCl
What is 2
300
A catalyst that slows a reaction is called________.
What is inhibitor.
300
Fragments of molecules that have at least one electron available for bonding are called...
What is radicals...
400
Photosynthesis is an example of a(n) _____________ chemical reaction in which plants use sunlight to make glucose and oxygen.
What is endothermic
400
Alkali metals react violently with water to form metal ions, hydroxide ions and....
What is hydrogen gas..
400
Suppose you were producing zinc chloride by the reaction Zn + 2 HCl --> ZnCl2 + H2. If you started with 4 moles of zinc, you would need_______moles of hydrogen chloride and you would produce _________moles of zinc chloride.
What is 8 ; 4
400
What are three actions that can be performed in order to increase the rate of a reaction?
What is Increase concentration, Increase Temperature, Increase surface area.
400
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.
What is 3; 6
500
Explain why energy is necessary to chemical reactions, and describe some common sources of energy.
Energy is necessary to break bonds that hold molecules together, so that the atoms can recombine and form other molecules. Energy may come from the sun, as added heat, or from the energy stored within the atoms and molecules themselves.
500
Aluminum undergoes a single-displacement retraction with copper(II) sulfate to form aluminum sulfate and...
What is copper
500
Why is the mole ratio an important concept for a scientist who frequently measure and mixes chemicals in the lab? Explain.
What is What is Because the mole ratio is derived from the balanced equation, if a scientist knows the equation that describes a reaction, and the atomic weights of the substances involved, he or she can determine the amount of each substance needed.
500
Use chemical principles to describe why we store food in a refrigerator to keep it from spoiling. Give at least two examples.
What is At lower temperatures, chemical reactions proceed more slowly and will not produce the acids that make spoiled milk taste bad. Also, mold will grow more slowly and will not produce the acids that make spoiled milk taste bad. Also, mold will grow more slowly because the fungi will carry out the chemical process of digestion more slowly.
500
Explain how the Haber process for producing ammonia is a good example of Le Chatelier's principle. N2 (gas) + 3H2 (gas) --> 2NH3 (gas) + heat
What is Le Chatelier's principle states that a rise in temperature favors the reactions that absorb energy and makes less ammonia. If you have less nitrogen gas, and reduce the pressure, Le Chatelier's principle predicts that less ammonia will be produced. So to produce the most ammonia, you should have less heat and more pressure, as in the Haber process.
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