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QUESTION 8 In the reaction of aluminum metal and oxygen gas to make aluminum oxide, how many moles of aluminum will react with 0.80 grams O2? a. 1.0 b. 19 c. 0.067 d. 0.033 e. 0.10
0.033
QUESTION 6 Fe2O3 (molar mass = 159.7 g/mol) reacts with CO (molar mass = 28.0 g/mol) according to the equation Fe2O3 + CO --> Fe + CO2 (unbalanced) When 145.7 g of CO reacts with excess Fe2O3, how many moles of Fe (iron) will be produced? 1. 10.4 mol Fe 2. 1.73 mol Fe 3. 3.47 mol Fe 4. 7.80 mol Fe 5. 2.60 mol Fe
3. 3.47 mol Fe
QUESTION 1 Balanced chemical equations imply which of the following? A. Numbers of molecules are conserved in chemical change. B. Numbers of atoms are conserved in chemical change. C. Volume is conserved in chemical change. D. A and B E. B and C
B. Numbers of atoms are conserved in chemical change.
The correct coefficients to balance the following reaction are, in order: I2O5 + H2S → I2 + SO2 + H2O A. 1, 1, 1, 1, 1 B. 2, 5, 2, 5, 5 C. 3, 5, 3, 5, 5 D. 1, 2, 1, 2, 1 E. 2, 4, 1, 4, 5
C. 3, 5, 3, 5, 5
QUESTION 11 What is the theoretical yield of bismuth when 460 g of Bi2O3 reacts with excess carbon as shown below? Bi2O3 + C(s) => Bi(s) + CO(g) (not balanced)
Correct 413 ± 1%
QUESTION 7 Aluminum and oxygen react according to the following equation: 4Al(s) +3O2(g) => 2Al2O3(s) What mass of Al2O3, in grams, can be made by reacting 4.6 g Al with excess oxygen? a. 35 b. 8.7 c. 1.2 d. 17 e. 2.4
Correct b. 8.7
QUESTION 6 How many moles of H2O (g) are produced when 4.3 grams O2 (g) are consumed? a. 75 b. 0.073 c. 0.25 d. 0.72 e. 140
Correct b. 0.073
QUESTION 5 When 0.340 mol of butane, C4H10, are burned with excess oxygen giving CO2 and H2O, how many moles of oxygen are consumed? a. 0.340 b. 0.0523 c. 13.0 d. 2.21 e. 6.50
Correct d. 2.21
QUESTION 9 A 20.0 g sample of CaCO3 was treated with aqueous H2SO4 producing calcium sulfate, water and 3.65 g of CO2(g) according to: CaCO3(s) + H2SO4(aq) => CaSO4(s) + H2O + CO2(g). What was the percent yield of CO2? a. 33.0 % b. 41.5 % c. 50.7 % d. 83.0 % e. 91.1%
Correctb. 41.5 %
QUESTION 10 According to the equation 2H2 + O2 => 2H2O, how many grams of water are produced if 10.0 g of O2 is consumed if the reaction's yield is 100%? a. 5.63 g b. 10.0 g c. 11.3 g d. 2.81 g e. 22.5 g
Correctc. 11.3 g
QUESTION 12 Iron can react with chlorine to form iron(II) chloride according to: Fe(s) + Cl2(g) => FeCl2(s) If you begin with 10.0 g of iron, a. you will need 10.0 g Cl2 for complete reaction and will produce 20.0 g of FeCl2. b. you will need 20.0 g Cl2 for complete reaction and will produce 30.0 g of FeCl2. c. you will need 12.7 g Cl2 for complete reaction and will produce 22.7 g of FeCl2. d. you will need 12.7 g Cl2 for complete reaction and will produce 20.0 g of FeCl2. e. you will need 25.4 g Cl2 for complete reaction and will produce 35.4 g of FeCl2.
Correctc. you will need 12.7 g Cl2 for complete reaction and will produce 22.7 g of FeCl2.
For the reaction P4O10(s) + 6H2O(l) → 4H3PO4(aq), what mass of P4O10 must be consumed if 5.95 × 1023 molecules of H2O are also consumed? A. 107 g P4O10 B. 280 g P4O10 C. 2.97 g P4O10 D. 46.7 g P4O10 E. 1.68 × 103 g P4O10
D. 46.7 g P4O10
QUESTION 5 In the reaction of aluminum metal and oxygen gas, aluminum oxide is formed. How many moles of O2 will react with 2.0 moles Al? a. 1.5 moles b. 1.0 moles c. 2.0 moles d. 3.0 moles e. 6.0 moles
a. 1.5 moles
Balance the following equation: B2O3(s) + HF(l) → BF3(g) + H2O(l) a. B2O3(s) + 6HF(l) → 2BF3(g) + 3H2O(l) b. B2O3(s) + H6F6(l) → B2F6(g) + H6O3(l) c. B2O3(s) + 2HF(l) → 2BF3(g) + H2O(l) d. B2O3(s) + 3HF(l) → 2BF3(g) + 3H2O(l) e. B2O3(s) + 6HF(l) → 2BF3(g) + 6H2O(l)
a. B2O3(s) + 6HF(l) → 2BF3(g) + 3H2O(l)
QUESTION 1 Consider a specific chemical reaction represented by the equation aA + bB → cC + dD. In this equation the letters A, B, C, and D represent chemicals, and the letters a, b, c, and d represent coefficients in the balanced equation. Reference: Ref 9-1 How many possible values are there for the quantity "c"? A. 2 B. infinite C. 4 D. 3 E. 1
b
QUESTION 2 When the following equation is balanced, what is the sum of the coefficients? Al2(SO4)3 + Ca(OH)2 → Al(OH)3 + CaSO4 A. 4 B. 9 C. 7 D. 8 E. 10
b
QUESTION 7 Caustic soda, NaOH, can be prepared commercially by the reaction of Na2CO3 with slaked lime, Ca(OH)2. How many grams of NaOH can be obtained by treating 1.350 kg of Na2CO3 with Ca(OH)2? a. 1788.8 g b. 1019 g c. 1.79 g d. 509.4 g e. 1.02
b. 1019 g
QUESTION 4 For the reaction P4O10(s) + 6H2O(l) → 4H3PO4(aq), what mass of P4O10 must be consumed if 5.95 × 1023 molecules of H2O are also consumed? A. 280 g P4O10 B. 2.97 g P4O10 C. 46.7 g P4O10 D. 1.68 × 103 g P4O10 E. 107 g P4O10
c
QUESTION 3 Balance the following equation: Ca3(PO4)2(s) + SiO2(s) + C(s) → CaSiO3(s) + CO(g) + P4(s) a. Ca3(PO4)2(s) + 3SiO2(s) + 8C(s) → 3CaSiO3(s) + 8CO(g) + P4(s) b. Ca3(PO4)2(s) + 3SiO2(s) + 14C(s) → 3CaSiO3(s) + 14CO(g) + P4(s) c. Ca3(PO4)2(s) + 3SiO2(s) + 8C(s) → 3CaSiO3(s) + 8CO(g) + 2P4(s) d. 2Ca3(PO4)2(s) + 6SiO2(s) + 10C(s) → 6CaSiO3(s) + 10CO(g) + P4(s) e. 2Ca3(PO4)2(s) + 6SiO2(s) + 10C(s) → 6CaSiO3(s) + 10CO(g) + 4P4(s)
d
