Unit 5 Test - Ch. 8-9
Which equation is not balanced?
2H2 + O2 -> H2O
Predict what happens when nickel is added to a solution of potassium chloride.
No reaction occurs
What is the ratio of the actual yield to the theoretical yield , multiplied by 100 % ?
Percent yield
To determine the limiting reactant in a chemical reaction, one must know the
available amount of each reactant.
What is the maximum possible amount of product obtained in a chemical reaction?
theoretical yield
In the equation 2KCO , → 2KCI + 302 , how many moles of oxygen are produced when 3.0 mol of KCIO3 decompose completely?
4.5mol
What is the name of a list of elements arranged according to the ease with which they undergo certain chemical reactions?
Activity series
Which of the following is a formula equation for the formation of carbon dioxide from carbon and oxygen?
C + O2 -> CO2
In what kind of reaction does a single compound produce two or more simpler substances?
Decomposition reaction
The reaction represented by the equation 2HgO(s) -> 2Hg(l) + O2(g) is a(n)
Decomposition reaction
A chemical formula written over the arrow in a chemical equation signifies
a catalyst for the reaction
In the equation 2Al(s)+3Fe(NO3)2(aq)---->3Fe(s) + 2Al(NO3)3(aq), iron has been replaced by
aluminium
The reaction represented by the equation 2KClO3(s) -> 2KCl(s) + 3O2(g) is a(n)
decomposition
In one type of synthesis reaction, an element combines with oxygen to yield a(n)
oxide
For the reaction represented by the equation 2Na + 2H2O → 2NaOH + H2, how many grams of sodium hydroxide are produced from 3.0 mol of sodium with an excess of water?
120 grams
In the reaction represented by th e equation N2 + 3H2 → 2NH3 , what is the mole ratio of nitrogen to ammonia ?
1:2
Ozone, O3, is produced by the reaction represented by the following equation: NO2(g)+O2(g)-->NO(g)+O3(g) What mass of ozone will form from the reaction 2.0 g of NO2 in a car's exhaust and excess oxygen?
2.1 g O3
For the reaction represented by the equation C + 2H → CH . how many moles of hydrogen are required to produce 10 mol of methane, CH4?
20 mol
For the reaction represented by the equation so , + H2O → H25 . how many grams of sulfuric acid can be produced from 200. g of sulfur trioxide and 100. g of water?
245g
What is the balanced equation when aluminium reacts with copper (II) sulfate?
2Al + 3CuSO4 ------> Al2(S04)3+3Cu
The Haber process for producing ammonia commercially is represented by the equation N2 ( g ) + 3H2 ( g ) → 2NH (2). To completely convert 9.0 mol hydrogen gas to ammonia gas, how many moles of nitrogen gas are required?
3.0mol
For the reaction represented by the cquation 2Na + 2H , 0 → 2NaOH + H2 , how many grams of hydrogen are produced if 120. g of sodium and 80. g of water are available?
4.5 g
In the reaction represented by the equation 2A10 → 4A1 + 302 what is the mole ratio of aluminum to oxygen?
4:3
For the reaction represented by the equation CH4 + 2O2 → CO2 + 2H2O, how many moles of carbon dioxide are produced from the combustion of 100. g of methane?
6.23 mol
For the reaction represented by the equation 2Na + Cl → 2NaC how many grams of sodium chloride can be produced from 500. g each of sodium and chlorine?
824 g
When the equation Fe3O4 + Al -> Al2O3 + Fe is correctly balanced, what is the coefficient of Fe?
9
For the reaction represented g of chlorine react with excess potassium by the equation Cl + 2KBr - 2KCI + Br2 , calculate the percentage yield if 200 . bromi de to produce 410. g of bromine.
91.0 %
percentage What is the ured amount of a product obtained from a chemical reaction?
Actual yield
Predict what happens when calcium metal is added to a solution of magnesium chloride.
Calcium chloride forms
In what kind of reaction do the ions of two compounds exchange places in aqueous solution to form two new compounds
Double-displacement reaction
The reaction represented by the equation Pb(NO3)2(aq) + 2KI(aq) -> PbI2(s) + 2KNO3(aq) is a
Double-displacement reaction
In writing a chemical equation that produces hydrogen gas, the correct representation of hydrogen gas is
H2
Given the equation 3A + 2B → 2C the starting mass of A, and its molar mass, and you are asked to determine the moles of C produced, your first step in solving the problem is the multiply the given mass A by
I mol A / molar mass A
If metal X is lower than metal Y in the activity series, then metal X
Loses electrons less readily than does metal Y
In the chemical equation 2Mg(s) + O2(g) ? 2MgO(s)
Mg represents the reagent magnesium
Magnesium bromide (aq) + chlorine (g) yields
MgCl2(aq) and Br2(l).
In the word equation, sodium oxide + water -> sodium hydroxide, the formula for sodium hydroxide is represented by
NaOH
Predict what happens when zinc is added to water
No reaction occurs
The reaction represented by the equation Mg(s) + 2HCl(aq) -> H2(g) + MgCl2(aq) is a
Single - displacement reaction
The reaction represented by the equation Cl2(g) + 2KBr(aq) -> 2KCl(aq) + Br2(l) is a(n)
Single displacemet
The equation A + BX -> AX + B is the general equation for a
Single-displacement reaction
which branch of chemistry deals with the mass relationships of elements in compounds and the mass relationships among reactants and products in chemical reactions?
Stoichiometry
The reaction represented by the equation 2Mg(s) + O2(g) -> 2MgO(s) is a
Synthesis reaction
What can be predicted by using an activity series?
Whether a certain chemical reaction will occur
When a solid produced by a chemical reaction separates from the solution it is called
a precipitate
The ability to an element to react is the element's
activity
According to the law of conservation of mass, the total mass of the reacting substances is
always equal to the total mass of the products
An element in the activity series can replace any element
below it on the list
Which observation does not indicate that a chemical reaction has occurred?
change in total mass of substances
To balance a chemical equation, it may be necessary to adjust the
coefficients
The equation AX -> A + X is the general equation for a
decomposition reaction
In what kind of reaction does one element replace a similar element in a compound?
displacement reaction
The equation AX + BY -> AY + BX is the general equation for a
double-displacement reaction
Which reactant controls the amount of product formed in a chemical reaction?
limiting reactant
A chemical reaction involving substances A and B stops when B is completely used. B is the
limiting reactant.
After calculating g the amount with the amount of B available, one can determine the of reactant B required to completely react with A, then comparing that amount
limiting reactant.
Each of the four types of reaction stoichiometry problems require using
mole ratio
A chemist interested in the efficiency of a chemical reaction would calculate the
percentage yield.
When the limiting reactant in a chemical reaction is completely used, the
reaction stops.
The coefficients in a chemical equation represent the
relative numbers of moles of reactants and products
In what kind of reaction do two or more substances combine to form a new compound?
synthesis reaction
The equation A + X -> AX is the general equation for a(n)
synthesis reaction
Which of the following would be investigated in reaction stoichiometry?
the mass of potassium required to produce a known mass of potassium chloride
To determine the limiting reactant in a chemical reaction involving known masses of A and B, one co could first calculate
the number of moles of B and the number of moles of A available.
In a double-displacement reaction, hydrogen chloride and sodium hydroxide react to produce sodium chloride. Another product is
water
In an equation, the symbol for a substance in water solution is followed by
(aq)
Which coefficients correctly balance the formula equation CaO + H2O -> Ca(OH)2
1,1,1
For the reaction represented by the equation 2H2 + 0 -> 2HO , how many grams of water are produced from 6.00 mol of hydrogen?
108g
Which reaction does not occur?
2HF(aq) + Cl2(g) -> F2(g) + 2HCl(aq)
The units of molar mass are
g/mol.
