warner quiz

Calculation of the theoretical yield does not necessarily require a balanced chemical equation.

FALSE

Percent yield depends on the:

All of the above

If the subscripts are correct in the formula, the molar mass can be calculated correctly.

yes

How many moles of iron(III) oxide are produced from 3.0 moles3.0 moles of oxygen and excess Iron Sulfide as described by the chemical equation below? 4FeS+5O2→2Fe2O3+4SO2

1.2 mol

Ammonia and copper oxide react to form copper, water and nitrogen as shown in the following reaction: 2NH3 (g) + 3CuO (s) → 3Cu (s) + 3H2O (l) + N2 (g) If a sample of 51.0 g of ammonia was reacted with excess copper oxide, how many moles of nitrogen would be produced? ___ moles N2 gas Your answer should be rounded to three significant figures. Do not include units in your answer.

1.5

In CaCO3+HCl→CaCl2+H2O+CO2CaCO3+HCl→CaCl2+H2O+CO2, how many liters of carbon dioxide gas, measured at STPSTP, can be obtained from 45.0 g of calcium carbonate?

10.1 L

How many calculation steps are required for mass-mass stoichiometry problems?

3

Calculate the mass of iron which will be converted into its oxide (Fe3O4)(Fe3O4) by the action of 20 grams20 grams of steam on it. 3Fe+4H2O→Fe3O4+4H2

46.66 grams

Aluminum reacts with chlorine gas to form aluminum chloride via the following reaction: 2Al + 3Cl2 → 2AlCl3 How many grams of aluminum chloride could be produced by reacting 34.0 g of aluminum and 39.0 g of chlorine gas? _____ g Your answer should be 3 significant figures. Do not include units in your answer.

48.9

The actual yield of a certain reaction is 38.0 g, while the theoretical yield is 50.0 g. Calculate the percent yield.

76 %

Aluminum reacts with sulfuric acid to produce aluminum sulfate and hydrogen. If 250 g250 g of aluminum sulfate is produced in the reaction, 19.71 g19.71 g of aluminium was used as reactant. Al+H2SO4→Al2(SO4)3+H2

FALSE

When the excess reactants have been used up, the limiting reactants remain in the reaction.

FALSE

If 120 g120 g of iron(III) chloride reacts with 82 g82 g of hydrogen sulfide according to the following reaction: 2FeCl3+H2S→2FeCl2+2HCl+S2FeCl3+H2S→2FeCl2+2HCl+S , then which of the following statements is true?

FeCl3FeCl3 is the limiting reagent

In PbO+2HCl→PbCl2+H2OPbO+2HCl→PbCl2+H2O, 13 g13 g of lead oxide is mixed with 6.4 g6.4 g of hydrochloric acid to produce lead chloride and water. Which of the following is true?

HCl acts as an excess reagent

In the reaction 3Fe(OH)2(aq)+2H3PO4(aq)→Fe3(PO4)2(s)+6H2O(l)3Fe(OH)2(aq)+2H3PO4(aq)→Fe3(PO4)2(s)+6H2O(l), if 6.40 g6.40 g of Iron(II) hydroxide reacts with 5.00 g5.00 g of phosphoric acid, which of the following is true?

Iron(II) hydroxide is the limiting reagent

The percent yield is determined by the mass used in a reaction and the mole ratios in the balanced equation.

TRUE

The theoretical yield of a reaction can be calculated from reaction stoichiometery.

TRUE

What contributes to a percent yield that is less than 100 %?

all of the above

Which of the following is/are true for mass-mass calculations?

all of the above

In mass-volume and volume-mass calculations, all gases are considered to be at standard ______ and pressure, also referred to as _________.

temperature, STP

The reaction below shows the decomposition of sodium azide into sodium metal and nitrogen gas. 2NaN3 (s)→2Na(s)+3N2 (g)2NaN3 (s)→2Na(s)+3N2 (g) An unknown amount of sodium azide (NaN3) reacts and produces 0.033 moles of nitrogen gas. What mass of sodium metal is produced? _____ g Your answer should be rounded to two significant figures. Do not include units in your answer.

.51

Use the equation for the production of ammonia by the Haber process (shown below).N2(g)+3H2(g)→2NH3(g)N2(g)+3H2(g)→2NH3(g)In a certain reaction, you start with 4.0 moles of nitrogen and 10.0 moles of hydrogen.How many moles of the excess reactant will be left over after the reaction?

0.67 mol

Given the following equation: CH4 + 2O2 → CO2 + 2H2O How many grams of CH4 are needed to react with 3.2 grams of O2? _____ g Your answer should be rounded to two significant figures. Do not include units in your answer.

0.8

Iodine is prepared by mixing sodium iodate with hydriodic acid. NaIO3+HI→I2+NaI+H2ONaIO3+HI→I2+NaI+H2O Calculate the mass of iodine which is produced using 32.8 g32.8 g of sodium iodate.

126.23 grams

How many grams of carbon disulfide will be produced if .012 kg of sulfur reacts with carbon?

14.2 g

How many grams of magnesium nitride is required to produce 25.00 g25.00 g of magnesium hydroxide? Mg3N2+H2O→Mg(OH)2+NH3

14.43 grams

Hydrogen and oxygen gas react to form water by the reaction below. O2+2H2→2H2OO2+2H2→2H2O What volume of oxygen gas is required to completely react with 30.0 L of hydrogen gas, assuming all volumes are measured at the same temperature and pressure conditions?

15.0 L

What mass of silver nitrate will react with 5.85 grams of sodium chloride to produce 14.35 grams of silver chloride and 8.5 grams of sodium nitrate?

17.0 grams

What is the percent yield for a reaction if we predicted the formation of 42.0 grams of cyclohexene and actually recovered only 7.6 grams?

18.1%

Find the mass of sodium acetate which is required to make 500 ml of 0.475 molar aqueous solution. The molar mass of sodium acetate is 82.0245 grams per mole.

19.45 grams

How much volume is occupied by one mole of a gas at STP?

22.4 L

Consider the following reaction: Cl2+Na2S→2NaCl+SCl2+Na2S→2NaCl+S The percent yield of sulfur when 71.0 g of Cl2 is reacted in excess Na2S solution is 73.0 %. What is the actual mass of sulfur yielded by this reaction? (Molar mass of S = 32.1 g/mol, molar mass of Cl2 = 71.0 g/mol) ___ g You answer should be rounded to three significant figures. Do not include units in your answer.

23.4

A reaction between aluminum hydroxide and hydrogen chloride gas produces aluminum chloride and water. The percent yield for the reaction in which 15.6 g of aluminum hydroxide is reacted in excess hydrogen chloride gas is 92.5 %. What is the actual yield of aluminum chloride?

24.6

Zinc metal reacts with copper sulfate through the following reaction: Zn+CuSO4→Cu+ZnSO4Zn+CuSO4→Cu+ZnSO4 The percent yield for a reaction in which 32.5 g of Zn is reacted in excess CuSO4 solution is 85.0 %. What is the actual yield of copper of this reaction? _____ g Your answer should be rounded to three significant figures. Do not include units in your answer.

26.9

Given the following equation: 8 Fe + S8 → 8 FeS What mass of iron is needed to react with 16.0 grams of sulfur? ___ g Your answer should be rounded to three significant figures. Do not include units in your answer.

27.9

Methane gas combusts according to the following chemical equation: CH4(g)+2O2(g)→CO2(g)+2H2O(l)CH4(g)+2O2(g)→CO2(g)+2H2O(l) 29.2 L of methane gas is combusted with 63.3 L of oxygen gas at STP. What volume of carbon dioxide is produced in the reaction? _____ L CO2

29.2

S+O2→SO2S+O2→SO2 1.60 g of O2 is reacted in excess sulfur (S) according to the above reaction. If the percent yield of the reaction is 95.0 %. What is the actual yield of SO2? ___ g Your answer should be rounded to three significant figures. Do not include units in your answer.

3.04

Use the reaction below for the reaction of dicyanoacetylene with ozone to produce carbon monoxide and nitrogen.3C4N2(g)+4O3(g)→12CO(g)+3N2(g)3C4N2(g)+4O3(g)→12CO(g)+3N2(g).What volume of CO is produced when 1.20 L of C4N2C4N2 reacts?

4.80 L CO

Use the following equation for the combustion of methane gas.CH4(g)+2O2(g)→CO2(g)+2H2O(l)CH4(g)+2O2(g)→CO2(g)+2H2O(l)In a certain reaction at STP, 29.2 L of methane is combusted with 63.3 L of oxygen.What volume of excess reactant remains after the reaction is complete? _____ L O2L O2 Your answer should be rounded to two significant figures. Do not include units in your answer.

4.9

Sulfur trioxide decomposes to sulfur dioxide and oxygen gas as shown in the following reaction: 2SO3 (g) → 2SO2 (g) + O2 (g) Given a 240.0 g sample of sulfur trioxide (MM = 80.1 g/mol), how many grams of oxygen (MM = 32.0 g/mol) are produced, assuming the decomposition goes to completion? ___ g Your answer should be rounded to three significant figures. Do not include units in your answer.

47.9

2NBr3 + 3NaOH → N2 + 3NaBr + 3HBrO How many NaBr formula units are formed when 50 NBr3 molecules and 57 NaOH formula units react? (Formula units are the equivalent of molecules for ionic compounds e.g. 1 NaBr or 1 NaOH is one formula unit.) ___ NaBr formula units

57

30.0 g30.0 g of chlorine gas is bubbled through liquid sulfur to produce liquid disulfur dichloride. How much product is produced in grams? Cl2+S→S2Cl2

57.0 grams

Hydrochloric acid and sodium hydroxide react as follows: HCl + NaOH → H2O + NaCl Calculate the mass of NaCl formed when 40.0 grams of HCl and 40.0 grams of NaOH react? Molar mass of HCl = 36.5 g/mol Molar mass of NaOH = 40.0 g/mol Molar mass of NaCl = 58.5 g/mol _____ g Your answer should be rounded to three significant figures. Do not include units in your answer.

58.5

Water decomposes to hydrogen and oxygen gas as shown in the following reaction: 2H2O (g) → 2H2 (g) + O2 (g) Given a 6.80 g sample of H2O (MM = 18.0 g/mol), how many grams of oxygen (MM = 32.0 g/mol) is produced, assuming the decomposition goes to completion?

6.04

4.8 g of sulfur and 5.4 g of aluminum react based on the chemical equation below and 4.5 g of aluminum sulfide (Al2S3) are recovered from the reaction, a small amount cannot be recovered. 3S + 2Al → Al2S3 Determine the percent yield of Al2S3. (Molar mass of S = 32.06 g/mol, molar mass of Al = 26.98 g/mol) ___ % Round your answer to the nearest whole number percent.

60

Si + 2Cl2 → SiCl4 What mass of SiCl4 is formed when 10.0 grams of Si and 60.0 grams of Cl2 react? Molar mass of SiCl4 = 169.8 g/mol Molar mass of Cl2 = 70.9 g/mol Molar mass of Si = 28.0 g/mol ___ g Your answer should be rounded to three significant figures. Do not include units in your answer.

60.6

Use the reaction below for the decomposition of sodium azide to sodium metal and nitrogen gas.2NaN3(s)→2Na(s)+3N2(g)2NaN3(s)→2Na(s)+3N2(g)What volume of nitrogen at STP is generated by the decomposition of 130.0 g NaN3NaN3?

67.2 L N2

Calculate the mass of the graphite that must be burned to produce 0.0264 kg of carbon dioxide.

7.2 grams

Chlorine and hydrogen gas react to form hydrogen chloride as shown in the following reaction: Cl2 (g) + H2 (g) → 2HCl (g) Given a 7.10 g sample of chlorine (MM = 71.0 g/mol), how many grams of hydrogen chloride (MM = 36.5 g/mol) is produced, assuming the reaction goes to completion?

7.30 g

Given the following equation: 2F2 + 2H2O → 4HF + O2 What mass of fluorine is needed to completely react with 3.6 grams of water? Molar mass of F2 = 38.00 g/mol Molar mass of H2O = 18.02 g/mol ___ g Your answer should be rounded to two significant figures. Do not include units in your answer.

7.6

Consider the following balanced equation: 2Fe(OH)3 → Fe2O3 + 3H2O How many grams of Fe2O3 are produced if 10.7 grams of Fe(OH)3 react in this way? The molar mass of Fe(OH)3 is 107 g/mol The molar mass of Fe2O3 is 159.7 g/mol Round your answer to the nearest integer

8 grams

Given the following equation: 4NO + 3O2 + 2H2O →4HNO3 2.4 moles of NO, 2.4 moles of O2, and 2.4 moles of H2O react and 2.0 moles of HNO3 are recovered from the reaction. What is the percent yield of this reaction? ___ % Your answer should be rounded to the nearest whole number. Do not include units in your answer.

83

Calculate the percent yield if the theoretical yield is 50.0 g of a product and the actual yield is 42.0 g.

84%

Consider the following reaction: 4P + 5O2 → P4O10 The percent yield of P4O10 when 6.20 g of phosphorus burns in excess oxygen is 67.0 %.What is the actual yield of P4O10? (Molar mass of P = 31.0 g/mol, molar mass of P4O10 = 284 g/mol) (Round your answer 3 significant figures e.g. 5.62) ___ grams

9.51

If the actual yield of a compound is 0.198 g and the theoretical yield is 0.217 g, find the percent yield.

91.20%

Which statement best describes the importance of balanced chemical equations while solving stoichiometry problems?

A balanced equation shows the reacting ratios of all substances involved in the reaction in terms of moles.

Identification of limiting reagents is not necessary in order to calculate the percentage yield of a reaction.

FALSE

In a chemical reaction, both the limiting reactant and the excess reactant are consumed at the same time.

FALSE

In order to use a volume ratio in a stoichiometry problem, the reaction must take place at STP.

FALSE

Nitrogen and oxygen react to form NO. 29.8 L of oxygen is required at STP, to produce 20.0 g of NO.

FALSE

Nitrogen is the limiting reagent in a reaction where 50.0 kg of nitrogen (g) reacts with 10.0 kg of hydrogen (g).

FALSE

The actual yield is always greater than the theoretical yield.

FALSE

The actual yield is calculated, while the theoretical yield is measured.

FALSE

The reactant which is consumed completely in a reaction is called the excess reactant.

FALSE

The weight of 11.2 liters of carbon dioxide at STP would be 44.0 g.

FALSE

Given the following equation: N2 + 3H2 → 2NH3 There are 1.0 moles of N2 and 2.0 moles of H2 reacting. Which is the limiting reactant?

H2

The Haber process generates ammonia from nitrogen and hydrogen gas through the following chemical equation. N2+3H2→2NH3N2+3H2→2NH3 Which is the excess reagent in the Haber reaction if equal moles of Hydrogen and Nitrogen are used?

N

Given the following equation: 2NO + 2CO → N2 + 2CO2 There are 3.0 g of NO and 3.0 g of CO reacting. What is the limiting reactant? ___ Your answer should be a molecular formula. (e.g. "NO" or "N2")

NO

In the following equation, there are 100 g Na100 g Na and 150 g of Fe2O3150 g of Fe2O3. Based on these measurements, which of the following are true? 6Na+Fe2O3→3Na2O+2Fe

NaNa is the limiting reagent

For the following reaction, given that nitrogen and hydrogen are present in equal volumes, 3H2+N2→2NH33H2+N2→2NH3, which of the statements is true?

Nitrogen is the excess reagent

7 g of trisodium phosphate is mixed with 12.8 g of barium nitrate to produce barium phosphate and sodium nitrate. In this reaction trisodium phosphate is the excess reagent and barium nitrate is the limiting reagent.

TRUE

All mass values are need to be converted to moles before determining the limiting reactant. Because the chemical equation gives the relationships among reactants as mole quantities.

TRUE

An excess reactant is the one which is present in an amount that is more than enough to react with the limiting reactant.

TRUE

Between the limiting reactant and the excess reactant, limiting reactant is used up first in a chemical reaction.

TRUE

For a gas-phase reaction where the temperature and the pressure remain constant, any mole ratio is equal to a volume ratio.

TRUE

If 1.2 g of ammonium bicarbonate is treated with .75 grams of sodium chloride, 63.0075 grams sodium bicarbonate will be produced. In this reaction NaCl is limiting reagent.

TRUE

If the units cancel and you are left with only the desired units for the problem, all the ratios were set up correctly.

TRUE

In a reaction where 3 grams of hydrogen reacts with 29 grams of oxygen to yield water, hydrogen will be the limiting reactant.

TRUE

In order to determine the limiting reactant for a chemical reaction, it is necessary to have a balanced equation.

TRUE

In order to use the molar volume of 22.4 L in a mass-volume or volume-mass stoichiometry problem, the gas must be assumed to be at STP.

TRUE

Standard ambient temperature and pressure is used as a reference with a temperature of 298.15 K and a pressure of 101 kPa.

TRUE

The actual yield of a compound is 3 grams, if the theoretical yield is 5 grams and the percent yield is 60 percent.

TRUE

The complete combustion of actylene gives carbon dioxide and water. 169 grams169 grams of carbon dioxide will be produced by the reaction of 50 grams50 grams of actylene. C2H2+O2→CO2+H2O

TRUE

The limiting reactants determine the maximum amount of product that can be formed.

TRUE

True or False: 2HgO → 2Hg + O2 Mercury, Hg, is prepared by heating 21.7 g of HgO, according to the above reaction. If the percent yield of the reaction is 84.6 %, the actual yield of Hg will be 17.0 g.

TRUE

When 1 mol1 mol of ZnZn reacts with 0.8 mol0.8 mol of HClHCl, which of the following will be true?

ZnZn is the excess reagent

In a chemical reaction, one of the chemical reactants is present in _____ to make sure that the limiting reagent is completely consumed.

excess

In the Haber reaction shown below, __________ is the limiting reactant if equal moles of each reactant are used. 3H2+N2→2NH3

hydrogen

What contributes to a percent yield that is greater than 100%?

impurities in the product

If some of the product of a chemical reaction couldn't be removed from the reaction vessel, its calculated percent yield would be ______ than it's theoretical yield.

lower

To convert from mass of A to liters of B in a stoichiometry problem, the following steps are followed:

mass A →→ moles A →→ moles B →→ liters B

To convert from mass of A to mass of B in a stoichiometry problem, the following steps are followed:

mass A →→ moles A →→ moles B →→ mass B

Which of these requires accurate coefficients in a reaction?

molar ratio

2Ag(s)+S(s)→Ag2S(s)2Ag(s)+S(s)→Ag2S(s) If we used 0.7 moles Ag and 0.312 moles S, would Ag be the limiting reactant?

no

6 moles of benzene react with 33.75 moles of oxygen to produce carbon dioxide through the chemical reaction below. 2C6H6+15O2→12CO2+6H2O2C6H6+15O2→12CO2+6H2O What is the limiting reactant in this reaction?

oxygen is the limiting reactant

The _____ yield is the maximum amount obtained when all of the limiting reagent has reacted in the balanced chemical equation.

theorhetical

For the gas phase reaction 3A(g)+B(g)→2C(g)3A(g)+B(g)→2C(g), which is NOT a valid conversion factor?

(2 g C / 1 g B)

Given the following equation: Na2O + H2O → 2 NaOH How many grams of Na2O are required to produce 1.60 × 102 grams of NaOH? ___ g Round your answer to the nearest whole number.

124

Given the following equation: 2KMnO4 → K2MnO4 + MnO2 + O2 How many grams of KMnO4 are required to produce 1.60 grams of O2? ___ g Your answer should be rounded to three significant figures. Do not include units in your answer.

15.8

Use the reaction below for the combustion of methanol. Any type of stoichiometry problem is possible.2CH3OH(l)+3O2(g)→2CO2(g)+4H2O(l)2CH3OH(l)+3O2(g)→2CO2(g)+4H2O(l)What mass of methanol is combusted in a reaction that produces 112 L of CO2CO2 at STP?

160. g CH3OH

Given the following equation: Cu + 2 AgNO3 → Cu(NO3)2 + 2 Ag How many grams of Cu would have to react to produce 89.5 grams of Ag? _____ g Your answer should be rounded to three significant figures. Do not include units in your answer.

26.4

Given the following equation: 2Al + 6HCl → 2AlCl3 + 3H2 If 3.00 grams of H2 were produced, how many grams of Al reacted? (Note: The molar mass of Al = 26.98 g/mol, and molar mass of H2 = 2.016 g/mol _____ g Al Your answer should be rounded to three significant figures. Do not include units in your answer.

26.8

Given the following equation: 2H2O → 2H2 + O2 How many grams of O2 are produced if 3.6 grams of H2O react? (Molar mass of O2 = 32 g/mol, molar mass of H2O = 18 g/mol)

3.2 g

10.0 g of calcium carbonate is treated with 10.0 g of HCl and, the percent yield of carbon dioxide is 79.5 percent. What is the actual yield of the product?

3.5 g

C3H8(g)+5O2(g)→3CO2(g)+4H2O(g)C3H8(g)+5O2(g)→3CO2(g)+4H2O(g) Assume if we combust 1.3 L of propane. How much CO2CO2 will be produced?

3.9 L

Methane combusts with oxygen through the following reaction: CH4 + 2O2 → CO2 + 2H2O How many grams of carbon dioxide are produced when 16.0 g of methane and 48.0 g of oxygen gas combust? Molar mass of CH4 = 16.0 g/mol Molar mass of O2 = 32.0 g/mol Molar mass of CO2 = 44.0 g/mol ___ g Your answer should be rounded to three significant figures. Do not include units in your answer.

33

Calculate the mass of slaked lime(calcium hydroxide) that would be required to completely decompose 8.00 g of ammonium chloride and what would be the mass of product of calcium chloride produced?

5.52 g of calcium hydroxide and 8.28 g of calcium chloride

Use the reaction below for the combustion of ammonia gas to produce nitrogen monoxide and water vapor.4NH3(g)+3O2(g)→4NO(g)+6H2O(g)4NH3(g)+3O2(g)→4NO(g)+6H2O(g)What volume of O2O2 is needed to react fully with 720. mL of NH3NH3?

540. mL O2

Given the following equation: CO2 + H2O → H2CO3 How many grams of CO2 are needed to react with 3.6 grams of H2O?

8.8 g

For the following reaction: CO + CuO → Cu + CO2 40 g of carbon oxide is reacted with 90 g of copper oxide. Which is the limiting reactant? (Molar mass of CO = 28 g/mol, molar mass of CuO = 80 g/mol)

CuO

The total mass of reactants used in a chemical reaction is often different than the total mass of products that can be recovered from that reaction.

FALSE

True or False: "3 atoms of iron combine with 3 molecules of oxygen to produce Fe3O4" The limiting reactant of the above chemical reaction is oxygen.

FALSE

10 g10 g of marble(calcium carbonate) was added to 15 g15 g of dilute hydrochloric acid, product formed is calcium chloride, water and carbon dioxide. Which of the following is true?

Hydrochloric acid is the excess reactant

CH3CH2OH+3O2→2CO2+3H2OCH3CH2OH+3O2→2CO2+3H2O What would be the limiting reactant in the reaction if 1 mole of oxygen gas and 1 mole of ethanol (CH3CH2OH) reacted with each other?

O

A reaction stops when all the limiting reactants are consumed.

TRUE