learnsmart chapter 10
Which of the following statements correctly describe a redox reaction?
-A redox reaction involves the transfer of electrons. -Reduction and oxidation must always occur together in redox reaction.
Which of the following statements about the molecular and empirical formulas of ionic and covalent compounds are true
-Formulas for covalent compounds are typically molecular formulas -Formulas for ionic compounds are never molecular formulas
Put in order, from top to bottom, the following steps necessary to calculate the mass percentage of oxygen in acetic acid (CH3COOH)
-calculate the formula weight of acetic acid from its formula. -multiply the number of atoms of oxygen in the molecular formula by the atomic weight of oxygen and then divide by the formula weight of acetic acid. -multiply the answer by 100 percent to find the mass percentage of oxygen in acetic acid.
A balanced chemical equation can be interpreted in terms of what types of rations between reactants and products?
-mass -molecular -mole
which of the following pieces of information are necessary to calculate the formula weight of a compound?
-the atomic masses of each of the elements that make up the compound -the chemical formula of a compound
which of the following options describe how to calculate the molecular/formula weight of a compound
-the atomic weight of a negative or positive ion is the same as the weight of the neutral element - for Ca(NO3)2, the subscript 2 must be multiplied by 3 to determine the total number of oxygen atoms in the compound. -The formula/molecular weight is given by the sum of the weights of the component elements in the correct proportions.
what is the meaning of a coefficient in a chemical equation?
-the number of molecules involved in the reaction. -the ratio of combining volumes of each substance (if all reactants and products are gaseous)
place the steps necessary to balance a chemical equation in correct order, starting with the first step at the top of the list
-write the formulas for the reactants and products -inventory the number and types of atoms -add coefficients in front of the reactants/products in order to balance the number of atoms -inventory the number and types of atoms and adjust coefficients such that there are the smallest whole number coefficients
the chemical formula of carbon tetrachloride (CCI4) tells us that this compound contains _____ carbon atoms and ____ chlorine atoms.
1;4
identify the coefficients required to balance the chemical equation. ___ SO2(g) + ____ O2 (g) ---> _____ SO3(g)
2;1;2
Which of the following equations will give the correct formula mass of the compound Fe(CIO4)2?
55.85u+2(35.45u)+8(16.00u)
which of the following correctly reflects Avogadro's number?
6.02x10^23 entities/mole
what is the general form of an ion exchange reaction?
AX+BY---> AY+BX
match each compound with the correct mass percentage of hydrogen C6H6 CH3OH CH2O
C6H6: 7.7% CH3OH: 12.6% CH2O: 6.71%
which two elements make up a molecule called a hydrocarbon?
Carbon; Hydrogen
which type of formula gives the simplest whole number ratio of atoms in a compound
Empirical Formula
Empirical formula Molecular formula Structural formula
Empirical formula: C2H5 Molecular: C4H10 Structural: (the picture)
To balance the reaction of hydrogen gas (H2) with oxygen gas (O2) to form liquid H2O, a student adds a subscript of 2 to the O in H2O. True or false: this is an acceptable method of balancing the above reaction.
False
Gram-atomic weight Gram- formula weight Gram-molecular weight
Gram Atomic- Mass in grams of 1 mole of an element that is numerically equal to its atomic weight Gram Formula- Mass in grams of 1 mole of the compound that is numerically equal to its formula weight Gram Molecular- Mass in grams of 1 mole of the molecule that is numerically equal to its molecular weight
which of the following balanced equations correctly represents the dissociation (dissolution) of K2SO4 in water?
K2SO4(s)---> 2 K+ (aq)+ SO4^2- (aq)
Which of the following species will present in an aqueous solution of Na3PO4
Na+ PO4 ^3-
NaBr MgSO4 KOH Al2O3
NaBr: 102.9g MgSO4: 120.4g KOH: 56.11g Al2O3: 102.0g
Oxidation Reduction
Oxidation-Loss of electrons by an atom Reduction- Gain of electrons by an atom
Reactants Products
Reactants- Substances that exist before a chemical reaction Products- Substances that exist after a chemical reaction
Match each general equation to the type of redox reaction it represents X+Y--> XY XY--> X+Y XY+Z-->XZ+Y
X+Y--> XY: combination XY--> X+Y: Decomposition XY+Z-->XZ+Y: Replacement
balance the illustrated chemical equation __AI2S3(s)+__H2O(i)--> __AI(OH)3(aq)+__H2S(g)
_1_AI2S3(s)+_6_H2O(i)--> _2_AI(OH)3(aq)+_3_H2S(g)
which of the following statements about coefficients and subscripts in a chemical equation is true?
coefficients can be changed when balancing a chemical equation.
a reaction in which two or more species combine to form a single compound is called a ____ reaction
combination
the ___ of a hydrocarbon in the presence of excess oxygen produces produces CO2 and H2O
combustion
the term molecular weight can only be applied to a __ compound since __ compounds do not consist of molecules. the correct term in this case is __ weight
covalent; ionic; formula
A reaction in which a compound is broken down into its elements, simpler compounds, or elements and simpler compounds is called a ____ reaction
decomposition
a chemical ___ uses symbols to describe concisely a chemical reaction.
equation
which of the following are possible products of an ion exchange reaction?
gas; water; solid
The mole relates the atomic weight of an element in u to the mass of 1 mole of that element expressed in ___.The mass of 1 mole of oxygen atoms is therefore equal to ___. (given to 3 digits and include the proper units)
grams; 16.0g
When an acid reacts with a base, the products are typically a ____ compound, which is called a ____, and the neutral molecule ____.
ionic;salt;water
When a soluble ionic compound is dissolved in solution, it dissociates into its respective ___
ions
a balanced chemical equation demonstrates the conservation of ___, as equal numbers of atoms are present on either side of the reaction.
mass
The ___ is defined as the amount of substance that contains the same number of entities as the number of ___ is exactly 12g of carbon-12
mole; atoms
A coefficient in a chemical equation has multiple meanings: it can tell you the number of _____ involved in the reaction and, for reactions in which the reactants and products are gaseous, the ____ of combining volumes at constant temperature and pressure.
molecules; ratios
2___ of H2 react with 1___ of O2 to produce 2____ of H2O. Choose the words that can properly complete this sentence describing the reaction 2H2(g)+O2(g)-->2H2O(I).
molecules;moles
The oxidation of one species allows the reduction of another, so the species being oxidized is called the ___ agent, whereas the species being reduced is the ___ agent.
reducing; oxidizing
Select all the metals that are expected to displace Cu in CuSO4, with reference to the activity series for metals
sodium; zinc
which of the following options correctly describe the formula weight of a compound?
the sum of the atomic weights of all the elements in the compound.
Gay-Lussac discovered that when gases combine at constant temperature and pressure, they do so in small __ number volumes. Avogadro reasoned that gases behave in this fashion because equal volumes of gas contain an equal number of ___.
whole; molecules
