Q&A Hero

Q: Which one of the following is necessary in order for a metal to be oxidized?A) addition of electronsB) removal of electronsC) addition of oxygenD) removal of oxygenE) addition of hydrogen

Q: Which of the following chemical reactions is an oxidation"reduction reaction?A) Zn(s) + S(s) → ZnS(s)B) H2SO4(aq) + 2NaOH(aq) → Na2SO4(aq) + 2H2O(l)C) NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)D) AgNO3(aq) + NaCl(aq) → AgCl(s) + NaNO3(aq)E) CO2(aq) + H2O(aq) → H2CO3(aq)

Q: All the following are oxidation"reduction reactions exceptA) H2(g) + F2(g) → 2HF(g).B) Ca(s) + H2(g) → CaH2(s).C) 2K(s) + 2H2O(l) → 2KOH(aq) + H2(g).D) 6Li(s) + N2(g) → 2Li3N(s).E) Mg3N2(s) + 6H2O(l) → 3Mg(OH)2(s) + 2NH3(g).

Q: Which of the following is an oxidation"reduction reaction?A) PbCO3(s) + 2HNO3(aq) → Pb(NO3)2(aq) + CO2(g) + H2O(l)B) Na2O(s) + H2O(l) → 2NaOH(aq)C) SO3(g) + H2O(l) → H2SO4(aq)D) CO2(g) + H2O(l) → H2CO3(aq)E) C2H4(g) + H2(g) → C2H6(g)

Q: Which of the following concerning oxidation-reduction reactions is/are correct? 1) Oxidation-reduction reactions always form gaseous products. 2) At least one substance is oxidized and one substance is reduced in an oxidation-reduction reaction. 3) The species that is oxidized loses one or more electrons in an oxidation-reduction reaction. A) 1 only B) 2 only C) 3 only D) 1 and 3 E) 2 and 3

Q: The balanced net ionic equation for the reaction of magnesium sulfite with nitric acid isA) MgSO3(s) + 2H+(aq) → Mg2+(aq) + SO2(g) + H2O(l).B) Mg2+(aq) + CO32-(aq) + 2H+(aq) + 2NO3-(aq) → Mg(NO3)2(aq) + SO2(g) + H2O(l).C) MgSO3(s) + 2HNO2(aq) → Mg2+(aq) + 2NO2-(aq) + SO2(g) + H2O(l).D) Mg(HSO3)2(s) + 2HNO3(aq) → Mg2+(aq) + 2NO3-(aq) + SO2(g) + 2H2O(l).E) MgSO3(s) + 2HNO3(aq) → Mg2+(aq) + 2NO3-(aq) + SO2(g) + H2O(l).

Q: In the reaction of acetic acid with aqueous sodium hydroxide, what is the spectator ion?A) OH-(aq)B) There is no spectator ion.C) C2H3O2-(aq)D) Na+(aq)E) H+(aq)

Q: What is the net ionic equation for the reaction that occurs between nitrous acid and strontium hydroxide?A) HNO2(aq) + OH-(aq) → NO2-(aq) + H2O(l)B) 2HNO2(aq) + Sr(OH)2 → Sr(NO2)2(aq) + H2O(l)C) 2H+(aq) + 2NO2-(aq) + Sr2+(aq) + 2OH-(aq) → Sr(NO2)2(aq) + H2O(l)D) 2H+(aq) + 2NO2-(aq) + Sr2+(aq) + 2OH-(aq) → Sr2+(aq) + 2NO2-(aq) + 2H2O(l)E) H+(aq) + OH-(aq) → H2O(l)

Q: The net ionic equation for the reaction of nitrous acid with lithium hydroxide isA) H+(aq) + OH-(aq) → H2O(l).B) HNO2(aq) + OH-(aq) → NO2-(aq) + H2O(l).C) HNO3(aq) + LiOH(aq) → LiNO3(aq) + H2O(l).D) HNO3(aq) + LiOH(aq) → Li+(aq) + NO3-(aq) + H2O(l).E) H+(aq) + NO2-(aq) + Li+(aq) + OH"(aq) → Li+(aq) + NO2-(aq) + H2O(l).

Q: Which of the following best represents the molecular equation for the reaction of aqueous ammonia with sulfuric acid?A) 2NH3(aq) + H2SO4(aq) → (NH4)2SO4(aq)B) NH3(aq) + H2SO4(aq) → NH4SO4(aq)C) NH4OH(aq) + H2SO4(aq) → NH4SO4(aq) + H2O(l)D) 2NH4+(aq) + H2SO4(aq) → (NH4)2SO4(aq) + 2H+(aq)E) 2NH4+(aq) + H2SO4(aq) → (NH4)2SO4(aq) + H2(g)

Q: One commercial system removes SO2 emissions from smoke at 95.0ºC by the following set of balanced reactions:SO2(g) + Cl2→SO2Cl2(g)SO2Cl2+ 2H2O →H2SO4+ 2HClH2SO4+ Ca(OH)2→CaSO4(s) + 2H2OAssuming the process is 95.0 % efficient, how many grams of CaSO4 may be produced from 100. g of SO2? (molar masses: SO2, 64.1 g/mol; CaSO4, 136 g/mol)A) 87.2 gB) 202 gC) 44.8 gD) 47.1 gE) 212 g

Q: Consider the fermentation reaction of glucose:C6H12O6→2C2H5OH + 2CO2A 1.00-mol sample of C6H12O6 was placed in a vat with 100 g of yeast. If 67.8g of C2H5OH was obtained, what was the percent yield of C2H5OH?A) 73.6 %B) 36.8 %C) 67.8 %D) 100 %E) none of these

Q: Nitric oxide, NO, is made from the oxidation of NH3, and the reaction is represented by the equation4NH3+5O2→4NO+6H2OAn 9.1-g sample of NH3gives 12.0 g of NO. The percent yield of NO is .A) 94 %B) 46 %C) 17 %D) 75 %E) 28 %

Q: Sulfur trioxide, SO3, is made from the oxidation of SO2, and the reaction is represented by the equation:2SO2+O2→2SO3A 21-g sample of SO2gives 18 g of SO3. The percent yield of SO3is .A) 11 %B) 69 %C) 17 %D) 26 %E) 100 %

Q: One step in the isolation of pure rhodium metal (Rh) is the precipitation of rhodium(III) hydroxide from a solution containing rhodium(III) sulfate according to the following balanced chemical equation:Rh2(SO4)3(aq)+6NaOH(aq)→2Rh(OH)3(s)+3Na2SO4(aq)If the reaction of 0.650g of rhodium(III) sulfate with excess sodium hydroxide produces 0.320g of rhodium(III) hydroxide, what is the percent yield?A) 316 %B) 158 %C) 39.5 %D) 49.2 %E) 79.0 %

Q: Pure copper may be produced by the reaction of copper(I) sulfide with oxygen gas as follows:Cu2S(s)+O2(g)→2Cu(s)+SO2(g)If the reaction of 0.630kg of copper(I) sulfide with excess oxygen produces 0.190kg of copper metal, what is the percent yield?A) 75.5 %B) 39.9 %C) 30.2 %D) 151 %E) 37.8 %

Q: Consider the following reaction:2A + B → 3C + D_3.0 mol A and 2.0 mol B react to form 4.0 mol C. What is the percent yield of this reaction?A) 75 %B) 67 %C) 89 %D) 50 %E) 100 %

Q: The reaction of 11.9 g of CHCl3with excess chlorine produced 10.2g of CCl4, carbon tetrachloride:2CHCl3+2Cl2→2CCl4+2HClWhat is the percent yield?A) 85.7 %B) 100 %C) 66.5 %D) 33.3 %E) 44.3 %

Q: A 5.95-g sample of AgNO3 is reacted with BaCl2according to the equation2AgNO3(aq)+BaCl2(aq)→2AgCl(s)+Ba(NO3)2(aq)to give 3.36g of AgCl. What is the percent yield of AgCl?A) 44.6 %B) 33.5 %C) 66.9 %D) 56.5 %E) 100 %

Q: One step in the isolation of pure rhodium metal (Rh) is the precipitation of rhodium(III) hydroxide from a solution containing rhodium(III) sulfate according to the following balanced chemical equation:Rh2(SO4)3(aq)+6NaOH(aq)→2Rh(OH)3(s)+3Na2SO4(aq)What is the theoretical yield of rhodium(III) hydroxide from the reaction of 0.590g of rhodium(III) sulfate with 0.266g of sodium hydroxide?A) 0.341 gB) 0.266 gC) 0.184 gD) 0.856 gE) 0.368 g

Q: If 48.8g of O2 is mixed with 48.8g of H2 and the mixture is ignited, what is the maximum mass of water that may be produced?A) 439 gB) 54.9 gC) 48.8 gD) 98 gE) 86.8 g

Q: When 20.0 g C2H6 and 60.0 g O2react to form CO2and H2O, how many grams of water are formed?A) 14.5 gB) 58.0 gC) 18.0 gD) 20.0 gE) none of these

Q: A 15-g sample of lithium is reacted with 15 g of fluorine to form lithium fluoride:2Li + F2→2LiF. After the reaction is complete, what will be present?A) 0.789 mol of lithium fluoride onlyB) 2.16 mol of lithium fluoride onlyC) 2.16 mol of lithium fluoride and 0.395 mol of fluorineD) 0.789 mol of lithium fluoride and 1.37 mol of lithiumE) none of these

Q: SO2reacts with H2S as follows:2H2S + SO2→3S + 2H2OWhen 7.50 g of H2S reacts with 12.75 g of SO2, which statement applies?A) 6.38 g of sulfur is formed.B) SO2is the limiting reagent.C) 0.0216 mol of H2S remains.D) 10.6 g of sulfur is formed.E) 1.13 g of H2S remains.

Q: The commercial production of phosphoric acid, H3PO4, can be represented by the equation1500 g 300 g 307 g 1180 g 300 gCa3(PO4)2 + 3SiO2+ 5C + 5O2+ 3H2O → 3CaSiO3+ 5CO2+ 2H3PO4310 g/mol 60.1 g/mol 12.0 g/mol 32.0 g/mol 18.0 g/molThe molar mass for each reactant is shown below the reactant, and the mass of each reactant for this problem is given above. Which substance is the limiting reactant?A) H2OB) CC) O2D) Ca3(PO4)2E) SiO2

Q: The limiting reactant is the reactant A) that has the lowest coefficient in the balanced equation. B) that has the lowest molar mass. C) that is left over after the reaction has gone to completion. D) for which there is the lowest mass in grams. E) none of the above

Q: Which of the following statements concerning the limiting reactant is/are correct? 1) The mass of the limiting reactant is the always the lowest mass of all reactant masses. 2) The theoretical yield depends on the amount of limiting reactant. 3) The moles of limiting reactant is always the lowest moles of all reactants. A) 2 only B) 3 only C) 1 and 3 D) 2 and 3 E) 1, 2, and 3

Q: Consider an initial mixture of CH4and O2represented in the container below:Given the reaction CH4+ 2O2→CO2+ 2H2O, which of the following represents a stoichiometric picture of the container after the reaction has gone to completion?A) B) C) D) E) none of the above

Q: A chemical reaction has the equation: 2A + B → C. In which case is B the limiting reactant?A) IIB) IC) IIID) IVE) none of these

Q: 2Al(s)+6HCl(aq)→2AlCl3(aq)+3H2(g)According to the equation above, how many grams of aluminum are needed to completely react with 3.83mol of hydrochloric acid?A) 310 gB) 46.6 gC) 34.4 gD) 3.83 gE) 103.3 g

Q: The balanced equation for the combustion of ethanol is2C2H5OH(g)+7O2(g)→4CO2(g)+6H2O(g)How many grams of dioxygen are required to burn 5.9g of C2H5OH?A) 14 gB) 21 gC) 4.1 gD) 38 gE) 55 g

Q: One step in the isolation of pure rhodium metal (Rh) is the precipitation of rhodium(III) hydroxide from a solution containing rhodium(III) sulfate according to the following balanced chemical equation:Rh2(SO4)3(aq)+6NaOH(aq)→2Rh(OH)3(s)+3Na2SO4(aq)If 0.620g of rhodium(III) hydroxide is produced, what mass of sodium sulfate is also produced?A) 0.572 gB) 0.930 gC) 0.858 gD) 0.620 gE) 0.381 g

Q: Pure copper may be produced by the reaction of copper(I) sulfide with oxygen gas as follows:Cu2S(s)+O2(g)→2Cu(s)+SO2(g)If 0.680kg of copper(I) sulfide reacts with excess oxygen, what mass of copper metal may be produced?A) 0.680 kgB) 0.136 kgC) 0.271 kgD) 0.543 kgE) 1.36 kg

Q: One step in the isolation of pure rhodium metal (Rh) is the precipitation of rhodium(III) hydroxide from a solution containing rhodium(III) sulfate according to the following balanced chemical equation:Rh2(SO4)3(aq)+6NaOH(aq)→2Rh(OH)3(s)+3Na2SO4(aq)What mass of sodium hydroxide is required to precipitate 74.0g of rhodium(III) hydroxide from a solution containing excess rhodium(III) sulfate?A) 6.41 gB) 57.7 gC) 19.2 gD) 222 gE) 74.0 g

Q: Pure copper may be produced by the reaction of copper(I) sulfide with oxygen gas as follows:Cu2S(s)+O2(g)→2Cu(s)+SO2(g)What mass of copper(I) sulfide is required in order to prepare 0.610kg of copper metal?A) 0.610 kgB) 0.305 kgC) 0.459 kgD) 1.53 kgE) 0.764 kg

Q: One step in the isolation of pure rhodium metal (Rh) is the precipitation of rhodium(III) hydroxide from a solution containing rhodium(III) sulfate according to the following balanced chemical equation:Rh2(SO4)3(aq)+6NaOH(aq)→2Rh(OH)3(s)+3Na2SO4(aq)If 2.40g of rhodium(III) sulfate reacts with excess sodium hydroxide, what mass of rhodium(III) hydroxide may be produced?A) 1.50 gB) 4.80 gC) 2.40 gD) 0.374 gE) 2.99 g

Q: Elemental sulfur can be converted to sulfur dioxide by combustion in air. Sulfur dioxide will react with water to form sulfurous acid (see balanced equation below).SO2(g)+H2O(l)→H2SO3(l)What mass of sulfur dioxide is needed to prepare 36.86g of H2SO3(l)?A) 28.77 gB) 47.23 gC) 0.5754 gD) 0.4491 gE) 36.86 g

Q: Calculate the number of moles of O2required to react with phosphorus to produce 4.76g of P4O6. (Molar mass P4O6= 219.9 g/mol) A) 0.0216 mol B) 0.149 mol C) 0.0649 mol D) 0.0433 mol E) 0.130 mol

Q: 2KHCO3(s)→K2CO3(s)+CO2(g)+H2O(l)How many moles of potassium carbonate will be produced if 454g of potassium hydrogen carbonate are heated?A) 2.27 molB) 3.29 molC) 11.4 molD) 227 molE) 4.54 mol

Q: Ammonia, NH3, and oxygen can be reacted together in the presence of a catalyst to form only nitrogen monoxide and water. The number of moles of oxygen consumed for every 5.00moles of NO produced is . A) 6.25 B) 25.0 C) 18.8 D) 3.13 E) 12.5

Q: The products of the combustion of acetone with oxygen are shown in the following equation:__CH3COCH3+__O2 → __CO2+__H2OWhen properly balanced, the equation indicates that ____ mol of CO2are produced for each mole of CH3COCH3.A) 3B) 5C) 4.5D) 8E) 1

Q: Balance the following expression:__CH3CH2COOH+__O2 → __CO2+__H2OHow many moles of O2are required for the complete combustion of 8 mol of propanoic acid?A) 5 molB) 30 molC) 28 molD) 37 molE) 2 mol

Q: The balanced chemical equation for the combustion of methane is:CH4(g) + 2 O2(g) → CO2(g) + 2 H2O(g)Which of the following statements concerning this chemical equation is/are correct?1) One gram of methane gas reacts with two grams of dioxygen gas, producing one gram of carbon dioxide gas and two grams of gaseous water.2) One mole of methane gas reacts with two moles of dioxygen gas, producing one mole of carbon dioxide gas and two moles of gaseous water.3) One molecule of methane gas reacts with two molecules of dioxygen gas, producing one molecule of carbon dioxide gas and two molecules of gaseous water.A) 1 onlyB) 2 onlyC) 2 and 3D) 1 and 3E) 1,2 and 3

Q: A chemical reaction has the equation: 2A + B ->C. Which of the following figures best illustrates a stoichiometric ratio of A and B?I. II. III. IV. A) I onlyB) III onlyC) II onlyD) Both I and IVE) IV only

Q: Complete combustion of a 0.30-mol sample of a hydrocarbon, CxHy, gives 1.20mol of CO2and 1.50mol of H2O. The molecular formula of the original hydrocarbon is A) C3H8. B) C4H10. C) C8H20. D) C3H5. E) C5H7.

Q: Analysis of a compound containing only C and Br revealed that it contains 33.33 % C atoms by numberand has a molar mass of 515.46g/mol. What is the molecular formula of this compound? A) CBr2 B) C2Br6 C) C2Br4 D) CBr3 E) C3Br6

Q: A molecular compound contains 92.3 % carbon and 7.7 % hydrogen by mass. If 0.432mol of the compound weighs 22.46g, what is its molecular formula? A) C8H8 B) C6H10 C) C4H8 D) C4H4 E) CH

Q: A compound contains 43.84 % carbon atoms, 3.65 % hydrogen atoms, and 8.68 % fluorine atoms by mass. Each molecule of this compound contains one fluorine atom. What is the total number of carbon, hydrogen, and fluorine atoms in one molecule of this compound? A) 17 B) 12 C) 9 D) 7 E) 14

Q: A compound has a molar mass of 171.6g/mol and contains 55.94 % oxygen atoms by mass. How many oxygen atoms are in each molecule of this compound? A) 6 B) 4 C) 10 D) 2 E) 8

Q: An organic compound has a molar mass of 171.1g/mol and contains 11.10 % hydrogen atoms by mass. How many hydrogen atoms are in each molecule of this compound? A) 19 B) 6 C) 21 D) 28 E) 11

Q: A compound is composed of only C and I. It contains 5.935 % C by mass and has a molar mass of 809.44g/mol. What is its molecular formula? A) CI B) C4I6 C) C3I4 D) C2I2 E) C2I3

Q: An unknown organic compound contains 41.4 % carbon, 3.47 % hydrogen, and 55.1 % oxygen by mass. A 0.040-mol sample of this compound weighs 3.48g. What is the molecular formula of the organic compound? A) C3H3O B) C2H2O2 C) C3H3O3 D) C7H7O7 E) CHO

Q: An organic compound has a molecular mass of 279.2 amu and contains 85.96% carbon by mass. How many carbon atoms are in each molecule of this compound?A) 16B) 21C) 25D) 29E) 20

Q: The empirical formula of styrene is CH. An experimental determination of the molar mass of styrene by a student yields the value of 104g/mol. What is the molecular formula of styrene? A) C5H10 B) CH C) C8H8 D) C3H8 E) C6H9

Q: The empirical formula of styrene is CH; its molar mass is 104.1 g/mol. What is the molecular formula of styrene? A) C6H6 B) C2H4 C) C8H8 D) C10H12 E) none of these

Q: The empirical formula for a group of compounds is CHCl. Lindane, a powerful insecticide, is a member of this group. The molar mass of lindane is 290.8. How many atoms of carbon does a molecule of lindane contain? A) 3 B) 2 C) 4 D) 6 E) 8

Q: A certain compound has a molar mass of 210g/mol. Which is a possible empirical formula for this compound? A) CH2O B) CHO C) C2H2O2 D) C2HO E) C2H2O

Q: An organic compound that has the empirical formula CHO has a molecular mass of 145 amu. Its molecular formula is A) C9H9O9. B) C4H4O4. C) C3H3O3. D) C5H5O5. E) C12H12O12.

Q: A given hydrocarbon is burned in the presence of oxygen gas and is converted completely to carbon dioxide and water. Equal numbers of moles of CO2and H2O are produced. The hydrocarbon could beA) C3H4.B) C5H10.C) C2H3.D) CH3.E) C3H5.

Q: A given hydrocarbon is burned in the presence of oxygen gas and is converted completely to water and carbon dioxide. The mole ratio of H2O to CO2is 1.33:1.00. The hydrocarbon could be A) C2H2. B) C2H6. C) CH4. D) C3H4. E) C3H8.

Q: The analysis of an organic compound showed that it contained 0.0700mol of C, 0.175mol of H, and 0.0350 mol of N. Its molecular mass is 86amu. How many atoms of carbon are there in the empirical formula for the compound, and how many are in the molecular formula? A) empirical = 2, molecular = 3 B) empirical = 2, molecular = 6 C) empirical = 2, molecular = 4 D) empirical = 5, molecular = 10 E) empirical = 3, molecular = 3

Q: A sample containing 0.700mol of a compound is composed of 4.21x1023atoms of sodium, 24.79g of chlorine atoms, and 33.57g of oxygen atoms. The formula of the compound isA) NaClO3.B) NaClO5.C) NaClO.D) NaClO4.E) NaClO2.

Q: The analysis of an organic compound showed that it contained 1.386mol of C, 0.0660mol of H, 0.924mol of O, and 0.462mol of N. How many nitrogen atoms are there in the empirical formula for this compound? A) 9 B) 7 C) 2 D) 4 E) 3

Q: What is the empirical formula of an oxide of nitrogen that contains 25.93 % nitrogen by mass? A) NO2 B) N2O C) N2O3 D) NO E) N2O5

Q: A particular compound contains, by mass, 41.4 % carbon, 3.47 % hydrogen, and 55.1 % oxygen. A 0.050-mol sample of this compound weighs 5.80g. The molecular formula of this compound is A) C3H3O3. B) C3H3O. C) CHO. D) C4H4O4. E) C5H5O5.

Q: A hydrocarbon, subjected to elemental analysis, was found to contain 85.63 % carbon and 14.37 % hydrogen by mass. What is the empirical formula of the hydrocarbon? A) CH4 B) C2H4 C) C6H D) C10H E) CH2

Q: A compound composed of only C and F contains 17.39 % C by mass. What is its empirical formula? A) CF3 B) CF C) C2F D) CF4 E) CF2

Q: A compound is composed of only C and H. It contains 92.26 % C. What is its empirical formula? A) C2H5 B) C2H3 C) C3H4 D) CH E) CH2

Q: A 2.39-g sample of an oxide of chromium contains 1.48g of chromium. Calculate the simplest formula for the compound. A) CrO5 B) Cr2O C) CrO2 D) CrO E) Cr2O3

Q: Chlorine was passed over 1.30g of heated titanium, and 4.20g of a chloride-containing compound of Ti was obtained. What is the empirical formula of the chloride-containing compound? A) TiCl2 B) TiCl4 C) TiCl D) TiCl3 E) Ti2Cl3

Q: A sample of an oxide of antimony (Sb) contained 39.5 g of antimony combined with 13.0 g of oxygen. What is the simplest formula for the oxide? A) SbO2 B) SbO C) Sb2O3 D) Sb2O E) Sb2O5

Q: Analysis of a compound showed that it contained 76.0 % fluorine atoms and 24.0 % carbon atoms by mass. What is its empirical formula? A) CF2 B) C2F3 C) CF3 D) C2F5 E) CF

Q: Which of the following is the empirical formula for the molecule below? A) CHO B) CH3COOH C) C2H4O2 D) CH2O E) none of the above.

Q: Of the following, the only empirical formula is A) C4H10. B) C4H6. C) C5H14. D) H2O2. E) O2.

Q: A sample containing only carbon, hydrogen, and silicon is subjected to elemental analysis. After complete combustion, a 0.1099-g sample of the compound yields 0.2193g of CO2, 0.1346 g of H2O, and 0.07485 g of SiO2. What is the empirical formula of the compound? A) CH3Si B) C2H4Si C) C4H12Si D) C6H12Si2 E) CH2Si

Q: A sample containing only carbon, hydrogen, phosphorus, and oxygen is subjected to elemental analysis. After complete combustion, a 0.4946-g sample of the compound yields 0.7092 g of CO2, 0.4355 g of H2O, and 0.3812 g of P4O10. What is the empirical formula of the compound? A) CH3PO B) C2H3PO C) C2H6P2O4 D) C3H9PO E) CH2P4O13

Q: A 0.4647-g sample of a compound known to contain only carbon, hydrogen, and oxygen was burned in dioxygen to yield 0.01962 mol of CO2and 0.01961 mol of H2O. What is the empirical formula of the compound? A) CHO B) C3H3O2 C) C2H2O D) C3H6O2 E) C6H3O2

Q: A 2.445 g sample of a hydrocarbon is burned in an excess of dioxygen, producing 6.708 g CO2 and 5.492 g H2O. What is the empirical formula of the hydrocarbon? A) CH4 B) CH2 C) C2H3 D) CH3 E) CH

Q: A 2.841 g sample of a hydrocarbon is burned in an excess of dioxygen, producing 7.794 g CO2 and water. What mass of hydrogen is contained in the original sample? A) 0.7140 g B) 4.953 g C) 10.64 g D) 2.826 g E) 1.421 g

Q: A 4.043 g sample of a compound containing only carbon, hydrogen, and oxygen is burned in an excess of dioxygen, producing 9.191 g CO2 and 3.762 g H2O. What percent by mass of oxygen is contained in the original sample? A) 27.54 % B) 37.96 % C) 12.73 % D) 13.43 % E) 6.939 %