Chemistry Quiz 5

Convert 56.04 mg to g using the factor label method. On the exam you have to write the correct equivalent statement and show the correct setup to get credit. Select one: a. 0.05604 g b. 0.056 g c. 56040 g d. 5.604 x 104 g

A.

Convert 76.0 J to kJ using the factor label method. On the exam you have to write the correct equivalent statement and show the correct setup to get credit. Select one: a. 0.076 kJ b. 0.0760 kJ c. 76000 kJ d. 7.60 x 104 kJ

B.

How many grams of Cl2 can be prepared from the reaction of 16.0 g of MnO2 and 30.0 g of HCl according to the following chemical equation? MnO2 + 4 HCl → MnCl2 + Cl2 + 2 H2O Select one: a. 0.82 g b. 5.8 g c. 13.0 g d. 16.0 g

C.

While calculating the number of moles of N2 in 78.92 g nitrogen, the equivalent statement to be used is 1 mol nitrogen = 14.01 g nitrogen. Select one: True False

False

Mole, which is a unit of amount, is an abbreviation for molecule which is an important term in chemistry. Select one: True False

False

Aluminum hydroxide reacts with nitric acid to form aluminum nitrate and water: Al(OH)3 + 3 HNO3 --> Al(NO3)3 + 3 H2O. What mass of water can be produced by the reaction of 15.0 g of aluminum hydroxide with excess nitric acid? (Hint: This kind of wording implies that aluminum hydroxide is the LR and all of it is assumed to react in order to calculate the theoretical yield as implied by 'can' in 'can be produced'.) Select one: a. 10.4 g b. 3.46 g c. 45.0 g d. 6.14 g

A.

Ammonia reacts with oxygen to form nitric oxide and water vapor: 4 NH3 + 5 O2 → 4 NO + 6 H2O When 20.0 g NH3 and 50.0 g O2 are allowed to react, which is the limiting reactant? Select one: a. NH3 b. O2 c. Neither reactant is limiting. d. NO

A.

Calculate the mass of 4.50 moles of chlorine gas, Cl2. Use the factor label method. On the exam you have to write the correct equivalent statement and show the correct setup to get credit. Select one: a. 319 g b. 4.50 g c. 15.7 g d. 160 g

A.

How many atoms are in 0.0728 g of PCl3? (Note: Calculate the total number of atoms of P and Cl.) Use the factor label method. On the exam you have to write the equivalent statement(s) and show the correct setup to get credit. Select one: a. 1.28 × 1021 atoms b. 4.38 × 1022 atoms c. 4.39 × 1021 atoms d. 3.19 × 1020 atoms

A.

How many atoms are in 4.39 g of CO2? (Note: Calculate the total number of atoms of C and O.) Use the factor label method. On the exam you have to write the equivalent statement(s) and show the correct setup to get credit. Select one: a. 1.80 × 1023 atoms b. 6.01 × 1022 atoms c. 1.16 × 1026 atoms d. 6.04 × 1024 atoms

A.

How many grams of silver nitrate are necessary to react completely with 7.000 moles of copper? Cu + 2 AgNO3 → Cu(NO3 )2 + 2 Ag Select one: a. 2379 g b. 238 g c. 14 moles d. not enough info given

A.

How many moles of HCl are represented by 1.0 × 1019 HCl molecules? Use the factor label method. On the exam you have to write the correct equivalent statement and show the correct setup to get credit. Select one: a. 1.7 × 10-5 b. 1.5 × 10-3 c. 1.0 × 1019 d. 36.5

A.

How many moles of phosphine (PH3 ) are produced for every 4.0 moles of hydrogen that react according to the chemical equation below? 3 H2 + P2 → 2 PH3 Select one: a. 2.7 mol b. 3.0 mol c. 5.4 mol d. 2.0 mol

A.

How many sulfur atoms are present in 25.6 g of Al2(S2O3)3? Use the factor label method. On the exam you have to write the equivalent statement(s) and show the correct setup to get credit. Select one: a. 2.37 × 1023 b. 6 c. 3.95 × 1022 d. 7.90 × 1022

A.

Hydrochloric acid can be prepared by the following reaction: 2 NaCl (s) + H2SO4 (aq) → 2 HCl (g) + Na2SO4 (s) 2.00 mol H2SO4 and 150 g NaCl are taken in a reaction vessel and the above reaction is conducted. If the actual yield of HCl is 62.9 g, calculate its percent yield. Select one: a. 67.3 % b. 41.9 % c. 3.15 x 103 % d. not enough information given

A.

Titanium is prepared by the following reaction taking place between 950 oC and 1150 oC. TiCl4 + 2 Mg --> Ti + 2 MgCl2. When 35.4 Mg TiCl4 is reacted with 11.3 Mg Mg in an industry, 7.91 Mg Ti is actually obtained. What is the percent yield obtained in this reaction? Select one: a. 88.4 % b. 11.3 % c. 35.4 % d. 7.91 %

A.

What is the formula mass of Ba3(PO4)2? Select one: a. 601.8 b. 601.84 c. 570.9 d. 570.87

A.

What is the mass of 0.0250 mol P2O5? Use the factor label method. On the exam you have to write the correct equivalent statement and show the correct setup to get credit. Select one: a. 3.55 g b. 5676 g c. 0.0250 g d. 1.51 × 1022 g

A.

What mass of O2 should completely react with 7.92 g N2O4 to produce 9.30 g N2O5 given the following equation 2 N2O4 + O2 --> 2 N2O5 ? Which law of chemical combination did you use in your calculation? Select one: a. 1.38; law of conservation of mass b. 17.22; law of definite proportions c. 1.38; law of definite proportions d. 17.22; law of conservation of mass

A.

Which of the following elements is/are made up of atoms and not molecules at RT/AP? (i) iodine (ii) potassium (iii) iron (iv) fluorine (v) argon Select one: a. ii, iii and v b. ii and iii c. iii only d. i and iv

A.

Which of the following is not a heteroatomic (or heteronuclear) molecule? Select one: a. O3 b. Al2S3 c. NO2 d. HNO3

A.

40.0 g of Cr2O3 and 8.00 g of aluminum are initally taken in a reaction vessel and allowed to react according to the chemical equation below. 2 Al + Cr2O3 → Al2O3 + 2 Cr If the actual yield of chromium obtained is 12.6 g, what is the percent yiled? Select one: a. 31.5 % b. 81.8 % c. 157 % d. not enough information given

B.

Ammonia reacts with oxygen to form nitric oxide and water vapor: 4 NH3 + 5 O2 → 4 NO + 6 H2O When 40.0 g NH3 and 50.0 g O2 are allowed to react, which is the limiting reactant? Select one: a. NH3 b. O2 c. Neither reactant is limiting. d. H2O

B.

Determine the number of moles of aluminum in 96.7 g Al. Use the factor label method. On the exam you have to write the correct equivalent statement and show the correct setup to get credit. Select one: a. 0.279 mol b. 3.58 mol c. 7.43 mol d. 4.21 mol

B.

How many grams of Cr can be produced by the reaction of 44.1 g of Cr2O3 with 35.0 g of Al according to the following chemical equation? 2 Al + Cr2O3 → Al2O3 + 2 Cr Select one: a. 7.56 g b. 30.2 g c. 67.4 g d. 104 g

B.

How many grams of nitrogen are there in 7.5 g of Ca(NO3)2? Use the factor label method. On the exam you have to write the equivalent statement(s) and show the correct setup to get credit. Select one: a. 0.64 g b. 1.3 g c. 0.15 g d. 1.15 g

B.

How many grams of sulfur are there in 6.0 g of Fe2(SO4)3? Use the factor label method. On the exam you have to write the equivalent statement(s) and show the correct setup to get credit. Select one: a. 2.4 g b. 1.4 g c. 6.0 g d. 0.92 g

B.

How many moles of CF4 are there in 171 g CF4? Use the factor label method. On the exam you have to write the correct equivalent statement and show the correct setup to get credit. Select one: a. 0.51 b. 1.94 c. 4.07 d. 88.0

B.

How many moles of O atoms are in 25.7 g of CaSO4? Use the factor label method. On the exam you have to write the equivalent statement(s) and show the correct setup to get credit. Select one: a. 0.189 mol b. 0.755 mol c. 4.00 mol d. 1.14 × 1023 mol

B.

How many moles of dichromate (Cr2O72-) ions are in 1 mole of Mn2(Cr2O7)3? Select one: a. 2 b. 3 c. 7 d. 14

B.

How many sulfur atoms (in the form of sulfide ions) are there in 21.0 g of Al2S3? Use the factor label method. On the exam you have to write the equivalent statement(s) and show the correct setup to get credit. Select one: a. 8.42 × 1022 atoms b. 2.53 × 1023 atoms c. 2.14 × 1023 atoms d. 6.02 × 1023 atoms

B.

One nanogram does not seem like a large amount. How many magnesium atoms are there in 1.00 ng magnesium? Use the factor label method. On the exam you have to write the correct equivalent statement(s) and show the correct setup to get credit. Select one: a. 4.11 × 10-11 b. 2.48 × 1013 c. 6.83 × 10-35 d. 6.02 × 1014

B.

Vanadium(V) oxide reacts with calcium according to the chemical equation below. When 10.0 moles of V2O5 are mixed with 10.0 moles of Ca, which is the limiting reactant? V2O5 (s) + 5 Ca (l) → 2 V (l) + 5 CaO (s) Select one: a. V2O5 b. Ca c. V d. No reactant is limiting.

B.

What is the mass of 8.25 × 1019 UF6 molecules? Use the factor label method. On the exam you have to write the correct equivalent statement(s) and show the correct setup to get credit. Select one: a. 352 g b. 0.0482 g c. 1.37 × 10-4 g d. 2.90 × 1022 g

B.

What is the mass of oxygen gas necessary to produce 200. g of sulfuric acid in the following reaction? 2 SO2 + O2 + 2 H2O → 2 H2SO4 Select one: a. 100. g b. 32.6 g c. 16.3 g d. 65.2 g

B.

What mass of sodium nitrate would be produced from the complete reaction of 1.00 mol of lead nitrate as per the following equation? 2 NaCl + Pb(NO3 )2 → 2 NaNO3 + PbCl2 Select one: a. 2.00 mol b. 170. g c. 340. g d. 85 g

B.

Which of the following elements is/are made up of diatomic molecules at RT/AP? (i) hydrogen (ii) copper (iii) sulfur (iv) bromine (v) carbon Select one: a. i only b. i and iv c. ii, iii and v d. iii and v

B.

Which of the following is a likely reason for a percent yield being greater than 100 % for a product of a reaction? Select one: a. The reaction is reversible and hence did not go to completion. b. The desired product was not completely dried before its mass was measured. c. Only a small amount of a particular reactant was used in the reaction. d. The separation method employed was not efficient enough and some of the desired product stayed in the reaction vessel itself.

B.

Which of the following is not a likely reason for a percent yield being less than 100 % for a product of a reaction? Select one: a. The reaction is reversible and hence did not go to completion. b. The desired product was not completely dried before its mass was measured. c. There was a side reaction undergone by the reactants in question. d. The separation method employed was not efficient enough and some of the desired product stayed in the reaction vessel itself.

B.

Which of the following samples contains the greatest number of atoms? Select one: a. 100.0 g Pb b. 2.0 mol Ar c. 0.1 mol Fe d. 20 million O2 molecules

B.

How many formula units are present in 87.5 kg of Ba3(PO4)2? Use the factor label method. On the exam you have to write the equivalent statement(s) and show the correct setup to get credit. Select one: a. 8.76 x 1022 b. 2.41 x 10-22 c. 8.76 x 1025 d. 2.41 x 10-25

C.

How many grams of sodium are there in 10. g of sodium sulfate, Na2SO4? Use the factor label method. On the exam you have to write the equivalent statement(s) and show the correct setup to get credit. Select one: a. 0.16 g b. 0.32 g c. 3.2 g d. 142 g

C.

How many molecules are there in 16 g ozone, O3? Use the factor label method. On the exam you have to write the correct equivalent statement and show the correct setup to get credit. Select one: a. 3 molecules b. 3.6 × 1024 molecules c. 2.0 × 1023 molecules d. 6.0 × 1023 molecules

C.

How many moles would 9.805 x 1025 atoms of Cu be? Use the factor label method. On the exam you have to write the correct equivalent statement and show the correct setup to get credit. Select one: a. 1.628 x 1048 b. 163 c. 162.8 d. 0.006142

C.

How many potassium ions are in 87.34 g potassium sulfite (K2SO3)? Select one: a. 6.646 b. 1.833 x 10-24 c. 6.646 x 1023 d. 1.833 x 1023

C.

How many sodium atoms (in the form of sodium ions) are there in 6.0 g of Na3N? Use the factor label method. On the exam you have to write the equivalent statement(s) and show the correct setup to get credit. Select one: a. 3.6 × 1024 atoms b. 4.6 × 1022 atoms c. 1.3 × 1023 atoms d. 0.217 atoms

C.

The phrase "1 mol hydrogen" is known to be ambiguous. Which of the following, do you think, should be the most appropriate reason? Select one: a. Because 1 mol is a unit of amount and not a unit of hydrogen. b. Because 1 mol is not exactly defined in chemistry. c. Because it can refer to either 6.022 x 1023 H atoms or H2 molecules. d. Because it can be 1 mol oxygen as well.

C.

What is the mass in mg of 7.9 x 1020 formula units of Ba3(PO4)2? Use the factor label method. On the exam you have to write the equivalent statement(s) and show the correct setup to get credit. Select one: a. 0.79 b. 7.9 c. 7.9 x 102 d. 7.9 x 1020

C.

What is the mass of water necessary to produce 200. g of sulfuric acid in the following reaction? 2 SO2 + O2 + 2 H2O → 2 H2SO4 Select one: a. 200. g b. 73.4 g c. 36.7 g d. 100. g

C.

Which of the following are ionic compounds? To answer this question correctly, use the color codes in the periodic table on the back of the front cover of our textbook to identify whether a given element is a metal, nonmetal or metalloid. (i) H2O (ii) C6H12O6 (iii) NaCl (iv) Cr2(SO4)3 (v) H3AsO4 (vi) Pb(NO3)4 (vii) LiAlH4 (viii) CO2 (ix) BF3 (x) SCl4 (xi) FeCl3 (xii) H2Te (xiii) CH3COOH (xiv) CH3COCH3 (xv) KAl(SO4)2 . 12 H2O Select one: a. i, ii, viii, x, xiii and xiv b. iii, iv, vi and xi c. iii, iv, vi, vii, xi and xv d. i, ii, v, viii, ix, x, xii, xiii and xiv

C.

Which of the following compounds are made up of formula units as their smallest units? Select one: a. i, ii, viii, x, xiii and xiv b. iii, iv, vi and xi c. iii, iv, vi, vii, xi and xv d. i, ii, v, viii, ix, x, xii, xiii and xiv

C.

Which of the following elements is made up of tetratomic molecules at RT/AP? Select one: a. nitrogen b. sodium c. phosphorus d. chlorine

C.

Which of the following is not a homonuclear molecule? Select one: a. P4 b. S8 c. HCl d. Cl2

C.

Calculate the mass of 1.21 × 1020 atoms of sulfur. Use the factor label method. On the exam you have to write the correct equivalent statement and show the correct setup to get credit. Select one: a. 3.88 × 1021 g b. 2.00 mg c. 32.06 g d. 6.44 mg

D.

Calculate the mass of excess reactant remaining at the end of the reaction in which 90.0 g of SO2 are mixed with 100.0 g of O2. 2 SO2 + O2 → 2 SO3 Select one: a. 11.5 g b. 22.5 g c. 67.5 g d. 77.5 g

D.

Calculate the mass of sodium chlorate that must be decomposed to form 6.5 g of oxygen according to the following equation. 2 NaClO3(s) → 2 NaCl(s) + 3 O2(g) Select one: a. 1.5 mol b. 7.0 g c. 56 g d. 14 g

D.

Convert 56.04 mg to kg using the factor label method. Check your class notes for the mnemonic diagram I drew on the board in relation to the conversion of one prefixed unit, pu1, to another, pu2. On the exam you have to write the correct equivalent statements and show the correct setup to get credit. Select one: a. 5.604 x 107 kg b. 5.604 x 105 kg c. 56.04 kg d. 5.604 x 10-5 kg

D.

How many atoms are in 5.54 g of F2? Use the factor label method. On the exam you have to write the equivalent statement(s) and show the correct setup to get credit. Select one: a. 6.02 × 1023 atoms b. 0.146 atoms c. 8.78 x 1022 atoms d. 1.76 × 1023 atoms

D.

How many fluorine atoms are there in 65 g of CF4? Use the factor label method. On the exam you have to write the equivalent statement(s) and show the correct setup to get credit. Select one: a. 0.74 atoms b. 3.0 atoms c. 4.5 × 1023 atoms d. 1.8 × 1024 atoms

D.

How many moles of Cl atoms are there in 65.2 g CHCl3? Use the factor label method. On the exam you have to write the equivalent statement(s) and show the correct setup to get credit. Select one: a. 0.548 mol b. 1.09 mol c. 3.3 × 1023 mol d. 1.64 mol

D.

How many moles of nitrate (NO3-) ions are in 82.9 g aluminum nitrate [Al(NO3)3]? Select one: a. 0.389 b. 7.03 x 1023 c. 7.71 d. 1.17

D.

How many moles of oxygen atoms are there in 10.0 moles of KClO3? Select one: a. 6.02 × 1024 mol b. 3.33 mol c. 10.0 mol d. 30.0 mol

D.

How many water molecules are present in 1 oz of water? Assume the density of water as 1.00 g/mL. 1 oz = 29.6 mL. Use the factor label method. On the exam you have to write the equivalent statements and show the correct setup to get credit. Select one: a. 2.73 x 10-24 b. 29.6 c. 1.78 x 1025 d. 9.89 x 1023

D.

If you have to use the molar mass of nicotine, C10H14N2 in further calculations, which of the following is the most appropriate to use? Select one: a. 162.2 g b. 162.23 g c. 162.232 g d. 162.232 g

D.

The molecular formula of aspirin is C9H8O4. How many aspirin molecules are present in one 500-milligram tablet? Assume the tablet to be pure aspirin, with no additives added. Use the factor label method. On the exam you have to write the correct equivalent statement(s) and show the correct setup to get credit. Select one: a. 2.77 b. 2.77 × 10−3 c. 1.67 × 1024 d. 1.67 × 1021

D.

What is the mass of sulfur dioxide necessary to produce 200. g of sulfuric acid in the following reaction? 2 SO2 + O2 + 2 H2O → 2 H2SO4 Select one: a. 200 g b. 2 mol c. 262 g d. 131 g

D.

What is the theoretical yield of vanadium, in moles, that can be produced by the reaction of 2.0 moles of V2O5 with 6.0 moles of calcium based on the following chemical equation? V2O5 (s) + 5 Ca(l) → 2 V (l) + 5 CaO (s) (Remember that in this kind of a problem you should first identify the LR. Caution: Don't decide on the LR by directly comparing the amounts of reactants given. It won't work. Remember to follow the strategy discussed in class.) Select one: a. 1.0 mol b. 1.6 mol c. 2.0 mol d. 2.4 mol

D.

What mass of N2 should completely react with 80.54 g H2O to produce 143.17 g NH4NO2 given the following equation N2 + 2 H2O --> NH4NO2 ? Which law of chemical combination did you use in your calculation? Select one: a. 223.71; law of conservation of mass b. 223.71; law of definite proportions c. 62.63; law of definite proportions d. 62.63; law of conservation of mass

D.

Which of the following are molecular compounds? To answer this question correctly, use the color codes in the periodic table on the back of the front cover of our textbook to identify whether a given element is a metal, nonmetal or metalloid. (i) H2O (ii) C6H12O6 (iii) NaCl (iv) Cr2(SO4)3 (v) H3AsO4 (vi) Pb(NO3)4 (vii) LiAlH4 (viii) CO2 (ix) BF3 (x) SCl4 (xi) FeCl3 (xii) H2Te (xiii) CH3COOH (xiv) CH3COCH3 (xv) KAl(SO4)2 . 12 H2O Select one: a. i, ii, viii, x, xiii and xiv b. iii, iv, vi and xi c. iii, iv, vi, vii, xi and xv d. i, ii, v, viii, ix, x, xii, xiii and xiv

D.

Which of the following compounds are made up of molecules as their smallest units? Select one: a. i, ii, viii, x, xiii and xiv b. iii, iv, vi and xi c. iii, iv, vi, vii, xi and xv d. i, ii, v, viii, ix, x, xii, xiii and xiv

D.

Which of the following is correct with respect to the formula of aluminum sulfate Al2(SO4)3? Select one: a. 1 mole of aluminum sulfate contains 4 moles of O atoms. b. 1 g of aluminum sulfate contains 3 g of S atoms. c. 6.022 x 1023 formula units of aluminum sulfate contain 6.022 x 1023 atoms of aluminum in the form of Al3+ ions. d. The subscript 3 is pronounced thrice to indicate that it is outside the parentheses.

D.

Which of the following is the most appropriate definition for molar mass of a substance? Select one: a. Molar mass is the mass of 1 mole of atoms. b. Molar mass is the mass of 1 mole of molecules. c. Molar mass is the mass of 1 mole of formula units. d. Molar mass is the mass of 1 mole of the relevant matter particles that make up the given substance.

D.