In a chemical reaction, the mass of the reactants equals _____ _____ _____ _____ _________.
A. the mass of the products
The signs of a chemical reaction or chemical change "may" indicate that a reaction has occurred, but the only way to truly know if a reaction has occurred is to find out ____ ___ _____ _____ ______ .
A. identity of reactants is different
A chemical equation is _______ when the same number of each kind of atom appears in the reactants and in the products.
A. balanced
The symbol triangle above a arrow in a chemical equation means ____ _____ _______.
A. heat is supplied
If a reaction is reversible, the ______ symbol will be used.
A. two horizontal arrows going opposite ways
A skeleton equation shows just the reactants and products whereas a _______ _______ shows the relative amounts of reactants and products.
A. balanced equation
In ________ reaction two or more substances combine to form a new compound.
A. synthesis
In a double- displacement reaction, the reactants are generally two _______ compounds in aqueous solution.
A. ionic
When a single compound produces two or more simpler substances, it is called a ________ reaction.
A. decomposition
In a double-displacement reaction, one of the products may ______ from solution.
A. precipitate
In a combustion reaction, one of the reactants is always _____.
A. O subscript 2
The compete combustion of a ______ such as C eight H eighteen produces carbon dioxide and water.
A. hydrocarbon
The product of a combination reaction is Ca(OH) two. If one of the reactants is H two , what is the other reactant?
A. CaO
Oxides of active metals, such as CaO react with water to produce ________.
A. metal hydroxide
An active metal and a halogen react to form an ______.
A. salt
Many metals hydroxides decompose when heated to yield metal oxides and ______.
A. water
When a metal chlorate is heated, it decomposes to yield a metal chloride and ________.
A. oxygen
In the equation 2Al(s) + 3Fe(NOthree)two(aq) ~ 3Fe(s) + 2Al(NOthree)three(aq), iron has been replaced by ______.
A. Al
The replacement of chlorine by fluorine in a salt is an example of a single- displacement reaction by ______.
A. halogens
In order to predict whether or not a single-displacement reaction takes place, you need to consult a chart that shows the ______ ______ of ________.
A. activity series of metal
In the activity series of metals, only metals ______ hydrogen will displace hydrogen from an acid.
A. above
The ______ _______ can predict whether a certain chemical reaction will occur.
A. activity series
Hf(s) + N2 (g) ~ Hf3N4(s)
A. synthesis
Mg(s) + H2SO4(aq) ~ MgSO4(aq) + H2(g)
A. single displacement
C2H6(G) + O2 (g) ~ CO2 (g) + H2O (g)
A. combustion
Pb(NO3)2(aq) + NaI(aq) ~ PbI2(s) + NaNO3(aq)
A. double displacement
Questions Not Done ~
Question #'s 20, 21, 22, 23, 26, 28, 29, 30, 31, 33, 34, 35, 36
What are the five signals that a chemical reaction is occurring?
Color change, a solid forms, bubbles, temperature change, flame.
What is a precipitation reaction?
In a precipitation reaction, a solid is forms separately from liquid.
What is solubility?
Solubility is the ability for a substance to dissolve in water.
What is the difference between an acid and a base?
An acid releases H+ ions into water. A base releases OH- ions into water
What is an oxidation-reduction reaction?
An oxidation-reduction reaction occurs when a metal transfers electrons to a non-metal.
In a chemical reaction, what are reactants and products?
Reactants are the substances before a chemical change, and products are substances after a chemical change.
Explain what a synthesis reaction is.
In a synthesis reaction, two substances come together to form one new substance.
Explain what a decomposition reaction is.
In a decomposition reaction, one substance breaks apart into two or more products.
What is a combustion reaction?
A combustion reaction is one in which the substance and oxygen burns. Carbon and water is released as a product.
Describe a single-displacement reaction.
In a single-displacement reaction, only one element switches to create a new product.
Describe a double displacement reaction.
In a double-displacement reaction, two compounds BOTH exchange ions and TWO NEW compounds are formed. (this can also be a precipitation reaction)
In a chemical reaction...
the mass of the reactants equals the mass of the products
Which observation does NOT indicate that a chemical reaction has occurred?
D. change in total mass of substances change in total mass of substances
When a solid produced by a chemical reaction seperates from the solution it is called
A precipitate
Which word equation represents the reaction that produces water from hydrogen and oxygen?
Hydrogen plus oxygen yields water
How would oxygen be represented in the formula equation for the reaction of methane and oxygen to ield carbon dioxide and water?
O2
In an equation, the symbol for a substance in water solution is followed by...
(aq)
When the equation Fe3O4 + AL (yields) Al2O3 + Fe is correctly balanced, what is the coefficient of Fe?
9
Which coefficients correctly balance the formula equation NH4NO2 (s) (yields) N2 (g) + H2O (l)?
1,1,2
Which coefficient correctly balance the formula equation CaO2 + H2O (yields) Ca(OH)2?
1,1,1
The reaction represented by the equation 2Mg(s) + O2 (g) (yields) 2MgO (s) is what kind of reaction?
Synthesis reaction
The reaction represented by the equation Mg (s) + 2HCl (aq) (yields) H2 + MgCl2 is what kind of reaction?
Single-displacement reaction
The reaction represented by the equation 2HgO (s) (yields) 2Hg (l) + O2 (g) is what kind of reaction?
decomposition reaction
The reaction represented by the equation Pb(NO3)2 (aq) + 2KI (aq) (yields) PbI2 (s) + 2KNO3 (aq) is what kind of reaction?
double-displacement reaction
The reaction represented by the equation 2KClO3 (s) (yields) 2Kcl (s) + 3O2 (gas) is what kind of reaction?
Decomposition reaction
The decomposition of a substance by an electric current is called...
Electrolysis
The replacement of bromine by chlorine in a salt is an example of a
single-displacement reaction by halogens
When a slightly soluble solid compound is produced in a double-displacement reaction, a
precipitate is formed
An insoluble gas that forms in a double-displacement reaction in aqueous solution
bubbles out of solution
In a double-displacement reaction, hydrogen chloride and sodium hydroxide react to produce sodium chloride.
Another product is water
If chlorine gas is produced by halogen replacement, the other halogen in the reaction must be
fluorine.
The formulas for the product of the reaction between sodium hydroxide and sulfuric acid are
Na2SO4 and H2O
What is the balanced equation when aluminum reacts with copper(II) sulfate?
2Al + 3CuSO4 (yields) Al2(SO4)3 + 3Cu
The activity series of metals indicated the ease with which
metal atoms lose electrons
Predict what happens when zinc is added to water
no reaction occurs
Predict what happens when lead is added to nitric acid
hydrogen is released
Predict what happens when nickel is added to a solution of potassium chloride
no reaction occurs