Chapter 5 Chem
Propane, C3H8, burns to produce carbon dioxide and water by the equation below. What is the coefficient in front of the carbon dioxide in the balanced equation? C3H8 + O2 → CO2 + H2O
3
The Haber Process is a method for the production of ammonia, an important chemical intermediate. The reaction for this process is: N2 + 3H2 → 2NH3. When the equation is correctly interpreted in terms of moles, how many moles of H2 will react with one mole of N2?
3
Tincture of iodine is an antiseptic. Which of the following is another antiseptic?
3% hydrogen peroxide
Which set of coefficients balances the equation? ____CH4→ ____C3H8 + ___H2
3,1,2
The Haber Process is a method for the production of ammonia, an important chemical intermediate. The reaction for this process is N2 + 3H2 → 2NH3. According to the mole interpretation, how many grams of NH3 could be produced by the complete reaction of 2.80 grams of N2 and excess H2?
3.40
In the reaction 2H2O → 2H2 + O2, 2.0 mol water will produce how many grams of O2?
32
Most reactions give a percent yield of almost 100%.
False
A REDOX reaction can also be a(n)
More than one response is correct.
2CO + O2 → 2CO2
False
A net ionic equation may include one or more spectator ions.
False
All redox reactions are exothermic reactions.
False
All redox reactions involve oxygen.
False
The oxidation number of cesium (Cs) is always +1.
False
The energy involved in chemical reactions
can take many forms
Acetylene, C2H2, burns according to the following reaction: C2H2+5O2 → 4CO2+2H2O. Suppose 1.20 g of C2H2 is mixed with 3.50 g of O2 in a closed, steel container, and the mixture is ignited. What substances will be found in the mixture left when the burning is complete?
C2H2, CO2, and H2O
If 5 grams of CO and 5 grams of O2 are combined according to the reaction, which is the limiting reagent? 2CO + O2 → 2CO2
CO
The oxidation number of iodine in HIO4 is +6.
False
Which of the following types of chemical reaction classes always involve oxidation?
single replacement
Lycopene, a phytonutrient, has several potential health benefits, including protection against prostate, cervical and pancreatic cancer. Which of the following is a good source of this substance?
tomatoes
Which ions will appear in the total ionic equation for the following reaction? Ba^2+ + CO ⅔ - + 2H^+ + SO 2/4- → CO2 + H2O + BaSO4
Ba2^+, CO ⅔-, H+, and SO 2/4-
What substance is oxidized in the following reaction? 4HCl + MnO2 → Cl2 + 2H2O + MnCl2
Cl in HCl
Which ions in the following reaction would be classified as spectator ions?
Cl-
Which of the following is a single replacement reaction?
CuO + H2 → Cu + H2O
In the reaction Zn + Cu(NO3)2 → Cu + Zn(NO3), the Zn is reduced.
False
Integers are used in properly balanced chemical equations because whole moles of substances are needed for a reaction.
False
Some redox reactions involve only oxidation without any reduction.
False
The reaction AgNO3 + HCl → AgCl + HNO3 is a redox reaction.
False
The reaction Mg + 3N2 → Mg3N2 is correctly balanced as written.
False
The reducing agent is the substance that is reduced in the reaction.
False
The ultimate source of all energy used by animals is the carbohydrates found in plants.
False
Which of the following contains the metal with the highest oxidation number?
FeCl3
Which of the following is a double replacement reaction?
HBr + KOH H2O + KBr
What is the reducing agent in the following reaction? 4HCl + MnO2 Cl2 + 2H2O + MnCl2.
HCl
Consider the reactants and propose the right side of the equation. Mg + H2SO4 → ____
MgSO4 + H2
What substance is reduced in the following reaction? 4HCl + MnO2 Cl2 + 2H2O + MnCl2
Mn in MnO2
What is the oxidizing agent in the following reaction? 4HCl + MnO2 Cl2 + 2H2O + MnCl2.
MnO2
When nitrogen (N2) reacts with sodium (Na), sodium nitride (Na3N) is formed. The balanced equation for the reaction would be:
N2 + 6 Na → 2Na3N
Which of the following is an oxidizing agent?
O2
Which of the following is a combination reaction?
SO2 + O2 --> 2SO3
A percentage yield greater than 100% has been reported in a scientific paper you are assigned to read. What would be a reasonable explanation for this?
Small measurement errors could have caused this to occur.
Consider the reactants in the partial equation given. Which choice is a product? H3PO4 + Sr(OH)2 →
Sr3(PO4)2
Automotive car batteries rely on the reaction shown below. Identify the spectator ion(s). PbO2(s) + 4 H+(aq) + 2 SO4^2- (aq) + Pb(s) → 2 PbSO4(s) + 2 H2O(l)
There are no spectator ions.
In which of the following does an element have an oxidation number of +4?
TiO2
In an exothermic reaction, heat is liberated to the surroundings.
True
In ionic compounds, metals have a positive oxidation number.
True
In the reaction CuCl2 + Fe → Cu + FeCl2 the CuCl2 is the oxidizing agent.
True
In the real world, one should not expect to obtain as much product as can be predicted from the stoichiometric calculation.
True
Products are always on the right side of a chemical equation.
True
Redox reactions may also be decomposition reactions.
True
A percentage yield less than 100% is often obtained in a reaction. What is(are) the reason for obtaining less than theoretically predicted?
all of the choices
The reaction below would be considered _____ . CaCO3 + heat → CaO + CO2
an endothermic decomposition.
Which of the following equations (not balanced) represents an oxidation-reduction process?
more than one response is correct
The modern definition of oxidation is a process
none of the choices.
When the following equation is balanced, how many oxygen atoms are present on the reactant side of the equation? C2H6 + O2 → CO2 + H2O
14
How many grams of N2 are required to completely react with 3.03 grams of H2 for the following balanced chemical equation? N2 + 3H2 → 2NH3
14.0
When the equation below is properly balanced, what coefficient is in front of KCl? KClO3 → KCl + O2
2
Which of the following is a decomposition reaction?
2H2O2 → 2H2O + O2
What is the oxidation number of Br in BrO2-?
+3
What is the oxidation number of Cl in HClO3?
+5
What is the assigned oxidation number for molybdenum in aluminum molybdate, Al2(MoO4)3?
+6
What is the oxidation number of Mn in KMnO4?
+7
Which of the following conversion factors would allow one to calculate the amount of PbI2 produced from a given amount of NaI in the following unbalanced reaction? Pb(NO3)2 + Nal → Pbl2 + NaNO3
1 molPbl2/ 2molNal
Oxygen can be prepared in the lab by heating potassium chlorate in the presence of a catalyst. The reaction is 2KClO3 → 2KCl + 3O2. How many moles of O2 could be obtained from one mole of KClO3?
1.5
Which species would be considered a spectator ion based on the following equation? Ba2+ + 2NO3 + 2Na+ + SO4^2+ → BaSO4(s) + 2NO3- + 2Na+
2NO3
What are coefficients needed to balance the following reaction? 2 CH4 + ____ O2 → ____ CO2 + ____ H2O
4,2,4
Suppose 2.43 g of magnesium is reacted with 3.20 g of oxygen: 2Mg + O2 → 2MgO. How many grams of MgO will be produced?
4.03
A container is filled with 4.0 g H2 and 5.0 g O2. The mixture is ignited to produce water according to the following equation. How much water is produced? 2H2 + O2 → 2H2O
5.6 g
Given the equation 2CO + O2 → 2CO2, how many grams of CO2 form if 34.0 grams of CO are combined with excess oxygen?
53.4
In the reaction 2CH4 + O2 → 2CO + 4H2, how many molecules of CO will be produced by the complete reaction of 1.60 grams of CH4?
6.02 x 10^22
Tests are to be conducted on new anti-cancer drug and you are to prepare a fresh supply for the human subject studies. You discover that you were able to produce 1.345 g of this substance although it was theoretically possible to make 1.433 g. What was the percent yield for this synthesis?
93.86 %
The batteries in an automobile contain lead plates, water, PbSO4 and H2SO4. The instructions with a battery charger state that when a car battery is being charged, there must be no flames or sparks. Hydrogen is liberated during the process and might explode on ignition. Therefore, the hydrogen released is an indication that a redox reaction occurs during the charging process.
True
The net ionic equation for the reaction H2SO4 + NaOH → Na2SO4 + H2O is H+ + OH → H2O.
True
The oxidation number of Cr in K2CrO4 is +6.
True
The reaction Ca + Cl2 → CaCl2 is a redox reaction.
True
The reactions NaOH + HCl → H2O + NaCl and Ca(OH)2 + 2HBr → 2H2O + CaBr2 have the same net ionic equation.
True
Water is a product when any inorganic acid reacts with any inorganic base.
True
While antiseptics and disinfectants are both antibacterials, only an antiseptic should be used on living tissue.
True
Which of the following statements is not true about the reaction? 2 CH4 + 3 O2→ 2 CO2 + 4 H2O
Water and carbon dioxide are products.
Which of the following reactions is correctly balanced?
Zn + 2HCl → H2 + ZnCl2
Barium sulfate is often ingested to aid in the diagnosis of GI tract disorders. The equation for its production is Ba2+ + SO BaSO4(s). What type of equation is this?
a net ionic equation
Airbags serve an important role in providing driver and front-seat passenger protection in the event of an automobile accident. They rely on several chemical reactions. Which of the following chemicals is responsible for N2 production?
more than one answer is correct
Consider the following chemical equation. Which substance is oxidized? BaCl2 (aq) + H2SO4 (aq) → BaSO4 (s) + 2HCl (aq)
none of them
In the equation for an endothermic reaction, the word "heat" appears
on the left side
Single replacement reactions are always
redox reactions
According to the law of conservation of matter, which of the following may NEVER occur as a result of a chemical reaction?
reduction in total mass.
The following would represent what type of chemical reaction?
single replacement
The reaction 2KBr + F2 2KF + Br2 is an example of a _____ reaction.
single replacement
Which is not a meaning of oxidation?
to gain electrons
Which of the following phrases can be used to describe the process of reduction?
to gain oxygen
For the reaction of HCl and NaOH, which of the following type of chemicals will appear in the net equation?
water
