Chem 0100 Exam 3 – Flashcards
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The reaction shown below is an example of a combustion reaction: HgO -----> Hg + O2 True or False?
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False
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What is the molar mass of Ca(ClO4)2?
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239.1 g/mol
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Which of the following compounds has a molar mass equal to 108 g/mol? SF2 SF3 SF4 SF6
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SF4
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The molar mass of a compound called cyclopentane is 70.0 g. One of the chemical formulas shown below is the correct formula for cyclopentane. Which one is it? C5H10 C6H12 C6H10 C5H16
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C5H10
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Consider the following chemical reaction. Br2 + 2 Cl- ----> Cl2 + 2 Br- The Br atoms in Br2 are oxidized in this reaction. True False?
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False
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Which statement describes an exothermic reaction? In an exothermic reaction, energy is given off and appears as a reactant. In an exothermic reaction, energy is absorbed and appears as a reactant. In an exothermic reaction, energy is given off and appears as a product. In an exothermic reaction, energy is absorbed and appears as a product.
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In an exothermic reaction, energy is given off and appears as a product.
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Which of the following has the largest mass? 5.0 moles of H2O 3.5 moles of NH3 8.0 moles of C 6.0 moles of C2H2
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6.0 moles of C2H2
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You have 8.13 x 1023 carbon atoms. How many moles is this equivalent to? 1.15 moles 1.25 moles 1.35 moles 1.45 moles
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1.35 moles
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What is the mass in grams of one mole of P2O5? 239.03 grams 61.96 grams 141.96 grams 46.98 grams
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141.96 grams
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What is the mass of 2.11 x 1022 molecules of CO2? 1.54 grams 2.11 x 1022 grams 1260 grams 0.981 grams
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1.54 grams
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How many molecules are present in 745 grams of oxygen gas, O2? 745 6.02 x 1023 1.40 x 1025 23,840
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1.40 x 1025
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How many silicon (Si) atoms are in 12.5 grams of silicon? 2.68 x 1023 5.83 x 10-22 1.35 x 1024 1.71 x 1021
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2.68 x 1023
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What is the oxidation number of N in the NO3- ion? +3 +5 -3 -5
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+5
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What is the oxidation number of Mn in MnO2? -4 -2 +2 +4
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+4
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What particle is transfered from one reactant to another reactant in an oxidation-reduction reaction? A proton An electron A hydronium ion A neutron
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An electron
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Lead (Pb) is oxidized in a chemical reaction. What is a possible product of this reaction? Pb2- Pb2+ Pb3+ More than one of the substances is a possible product in the reaction
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More than one of the substances is a possible product in the reaction
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The oxidation of carbon (C) can form carbon dioxide (CO2). True False
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True
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Determine the percent composition of FeTiO3. What is the percentage of titanium in this compound? 20% 32% 80% 68%
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32%
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Determine the percent composition of Fe2O3. What is the percentage of iron in this compound? 40% 60% 70% 30%
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70%
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Balance the following chemical equation. K + H2O ----> KOH + H2 3K + 3 H2O ---> 3 KOH + H2 K + H2O ---> KOH + H2 2 K + 2 H2O ---> 2 KOH + H2
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2 K + 2 H2O ---> 2 KOH + H2
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You add heat to an ice cube to melt it. This proces is: Exothermic Endothermic Neither exothermic nor endothermic Endothermic and exothermic
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Endothermic
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Balance the following chemical equation. Na(s) + H2O ---> NaOH(s) + H2 Na(s) + H2O ---> 2 NaOH(s) + 2 H2 2 Na(s) + 2 H2O ---> 2 NaOH(s) + H2 Na(s) + H2O ---> NaOH(s) + 2 H2 2 Na(s) + H2O ---> NaOH(s) + 2 H2
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2 Na(s) + 2 H2O ---> 2 NaOH(s) + H2
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Balance the chemical equation shown below: VCl2 + Cl2 ---> VCl5. 1 VCl2 + 3 Cl2 ---> 2 VCl5 3 VCl2 + 4 Cl2 ---> 3 VCl5 1 VCl2 + 2 Cl2 ---> 1 VCl5 2 VCl2 + 3 Cl2 ---> 2 VCl5
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2 VCl2 + 3 Cl2 ---> 2 VCl5
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The chemical equation shown below is correctly balanced. Zn + 2HCl ---> H2 + ZnCl2 True False
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True
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What is the number or coefficient in front of the "CH4" when the following chemical equation is balanced? CH4 + O2 -----> CO2 + H2O 0 1 2 4
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1
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Calculate the percent composition of magnesium hydrogen sulfate. The formula for magnesium hydrogen sulfate is Mg(HSO4)2. 27.85% Mg, 23.31% S, 38.89% O, 9.95% H 11.13% Mg, 29.35% S, 58.59% O, 0.92% H 26.45% Mg, 28.42% S, 43.68% O, 1.45% H 46.82% Mg, 12.67% S, 38.30% O, 2.21% H
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11.13% Mg, 29.35% S, 58.59% O, 0.92% H
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50.0 grams of KBr corresponds to 0.0420 moles of KBr. True False
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False
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Find the mass of 7.35 x 10 22 molecules of titanium(IV) bromide. The formula for titanium(IV) bromide is TiBr4. 44.9 g 449 g 0.022 g 0.222 g
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44.9 g
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1.000 mole of H2O corresponds to 0.05549 grams of H2O. True False
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False
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Consider the chemical reaction shown below: Zn + 2 H+ ---> Zn2+ + H2 The H+ is reduced in this reaction. True False
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True
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A reducing agent is a substance that gains electrons during a chemical reaction. True False
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False
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Consider the chemical reaction shown below: 2 Mg + O2 ---> 2 Mg2+ + 2 O2- Which statement is correct about this reaction? Mg is oxidized Mg is reduced O2 is oxidized None of the statements shown above are correct
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Mg is oxidized
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Balance the following chemical reaction. CaO + H3PO4 ----> Ca3(PO4)2 + H2O 3 CaO + 2 H3PO4 ---> Ca3(PO4)2 + 3 H2O 2 CaO + 2 H3PO4 ---> 2 Ca3(PO4)2 + 3 H2O CaO + 3 H3PO4 ---> Ca3(PO4)2 + 2 H2O 2 CaO + H3PO4 ---> 2 Ca3(PO4)2 + 2 H2O
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3 CaO + 2 H3PO4 ---> Ca3(PO4)2 + 3 H2O
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Balance the following chemical equation. CaH2 + H2O ---> Ca(OH)2 + H2 CaH2 + H2O ---> 2 Ca(OH)2 + 2 H2 CaH2 + 2 H2O ---> Ca(OH)2 + 2 H2 CaH2 + H2O ---> Ca(OH)2 + 2 H2 2 CaH2 + H2O ---> Ca(OH)2 + 2 H2
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CaH2 + 2 H2O ---> Ca(OH)2 + 2 H2
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What is the oxidation number of Cl in HCl? +1 0 -1 +2
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-1
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What is the oxidation number of S in H2SO3? +1 +2 +3 +4
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+4
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50.0 grams of MgBr2 corresponds to 2.71 moles of MgBr2. True False
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False
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How many moles are in 4.06 x 1025 molecules of sodium fluoride? 6.4 67.4 0.0198 0.198
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67.4
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What is the mass in grams of 3.46 moles of chlorine gas? The formula for chlorine gas is Cl2. 45.78 g 8.45 g 245 g 120.54 g
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245 g
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18.0 grams of c6h12o6 corresponds to: 0.100 moles of C6H12O6 0.0100 moles of C6H12O6 0.200 moles of C6H12O6 1.00 mole of C6H12O6
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0.100 moles of C6H12O6
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What is the molar mass for glucose which has the molecular formula C6H12O6? 29.0 g 72.1 g 180.0 g 348.4 g
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180.0 g
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The molar mass of a compound called cyclopentane is 70.0 g. One of the chemical formulas shown below is the correct formula for cyclopentane. Which one is it? C5H10 C6H12 C6H10 C5H16
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C5H10
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What is the molar mass of NaClO2. 74.5 g/mol 90.5 g/mol 110 g/mol 149 g/mol
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90.5 g/mol
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How many grams of sulfur (S) make up 3.01 moles of sulfur? 1.81 x 1024 grams 0.150 grams 32.06 grams 96.5 grams
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96.5 grams
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How many molecules are present in 13.4 grams of CO2? 5.06 x 1023 1.83 x 1023 9.79 x 1024 3.55 x 1026
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1.83 x 1023
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How many moles of sodium are equivalent to 4.37 x 1018 atoms of sodium? 6.02 x 1023 moles 2.63 x 1042 moles 1.23 x 1017 moles 7.26 x 10-6 moles
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7.26 x 10-6 moles
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How many atoms are in 2.4 grams of magnesium? 6.0 x 1022 3.7 x 1022 2.5 x 1022 1.7 x 1022
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6.0 x 1022
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What is the mass of 500 moles of magnesium oxide, MgO? 40 grams 500 grams 20152 grams 3.01 x 1026 grams
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20152 grams
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Which of the following has the largest mass? 5.0 moles of H2O 3.5 moles of NH3 8.0 moles of C 6.0 moles of C2H2
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6.0 moles of C2H2
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The reaction shown below is an exothermic reaction: H2 + CO2 + 9.80 kcal -----> H2O + CO True False
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False
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Calculate the percent composition of Al2(SO4)3. What is the percentage of sulfur in this compound? 28.1 % sulfur 96.3 % sulfur 342.3 % sulfur 9.4 % sulfur
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28.1 % sulfur
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What is the percent composition of hexane (C6H14)? 83.6% hydrogen and 16.4% carbon 16.4% hydrogen and 83.6% carbon 14.0% hydrogen and 86% carbon 72.0% hydrogen and 28% carbon
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16.4% hydrogen and 83.6% carbon
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The following chemical equation is correctly balanced. C6H14 + 13 O2 -----> 6 CO2 + 7 H2O True False
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False
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What is the number or coefficient in front of the "CO" when the following equation is balanced? C3H8 + O2 -----> CO + H2O 1 3 6 12
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6
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When you balance the following chemical equation, the coefficient for Rb is "3". Rb + H2O ---> Rb2O + H2 True False
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False
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Consider the following chemical reaction. C2H4 + 3 O2 ----> 2 CO2 + 2 H2O The O atoms in O2 are oxidized in this reaction. True False
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False
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What is the mass of 0.0400 moles of K2CO3? 3.96 grams 4.12 grams 5.53 grams 6.36 grams
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5.53 grams
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How many molecules are present in 745 grams of oxygen gas, O2? 745 6.02 x 1023 1.40 x 1025 23,840
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1.40 x 1025
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How many carbon atoms (symbol C) are in 2.50 moles of carbon? 2.5 atoms 6.02 x 1023 atoms 1.51 x 1024 atoms 15 atoms
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1.51 x 1024 atoms
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What is the mass of 0.0500 moles of Al2(SO4)3? 6.15 grams 10.95 grams 17.1 grams 19.8 grams
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17.1 grams
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You have 8.13 x 1023 carbon atoms. How many moles is this equivalent to? 1.15 moles 1.25 moles 1.35 moles 1.45 moles
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1.35 moles
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The reaction shown below is an endothermic reaction: 2 NH3 + 22.0 kcal -----> N2 + 3 H2 True False
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True
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Determine the percent composition of CH4O. What is the percent of carbon in this compound? 63% 50% 20% 38%
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38%
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Determine the percent composition of SeCl6. What is the percentage of chlorine in the compound? 35.7% 47.2% 64.3% 72.9%
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72.9%
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What is the oxidation number of C in CH4? +4 +2 -4 -2
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-4
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What is the oxidation number of Na in the Na+ ion? +1 0 -1 +2
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+1
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Balance the chemical equation shown below: MoF3 + F2 ---> MoF6 2 MoF3 + 2 F2 ---> 2 MoF6 1 MoF3 + 4 F2 ---> 1 MoF6 3 MoF3 + 2 F2 ---> 3 MoF6 2 MoF3 + 3 F2 ---> 2 MoF6
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2 MoF3 + 3 F2 ---> 2 MoF6
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What is the oxidizing agent in the reaction shown below: CH4 + 2 O2 -----> CO2 + 2 H2O CH4 O2 H2O This reaction does not have an oxidizing agent
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O2
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Balance the following chemical reaction. Mg + N2 ---> Mg3N2 3 Mg + 2 N2 ---> Mg3N2 2 Mg + 2 N2 ---> Mg3N2 3 Mg + N2 ---> Mg3N2 None of the answers shown above are correct
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3 Mg + N2 ---> Mg3N2
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What is the oxidizing agent in the reaction shown below: Sn2+ + 2 Fe2+ -----> Sn + 2 Fe3+ Sn2+ Fe2+ Sn Fe3+
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Sn2+
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To convert between moles and numbers of atoms in a substance, _______ must be used in the calculation. formula masses mole ratios atomic masses Avagadro's number
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Avagadro's number
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What is the molar mass of carbon dioxide (CO2)? 28.01 g/mol 44.01 g/mol 12.01 g/mol 16.00 g/mol
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44.01 g/mol
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10.0 moles of He corresponds to: 10.0 gram of He 20.0 grams of He 40.0 grams of He 80.0 grams of He
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40.0 grams of He
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What is the molar mass of (NH4)2SO3? 48.0 g/mol 116.1 g/mol 32.1 g/mol 48.0 g/mol
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116.1 g/mol
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What is the molar mass for glucose which has the molecular formula C6H12O6? 29.0 g 72.1 g 180.0 g 348.4 g
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180.0 g
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Determine the percent composition of C3H10N2. What is the percentage of carbon in this compound? 48.6% 13.6% 37.8% 65.2%
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48.6%
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Consider the chemical reaction shown below: Cu2+ + O2- + H2 ---> Cu + H2O In this reaction the Cu2+ is oxidized. True False
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False
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Consider the chemical reaction shown below. The Fe3+ ion in Fe2O3 is oxidized in this reaction. 2 Fe2O3 -----> 4 Fe + 3 O2 True False
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False
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10.0 grams of CaCO3 corresponds to 0.0100 moles of CaCO3. True False
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False
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100 grams of H2 corresponds to: 100 moles of H2 50 moles of H2 25 moles of H2 200 moles of H2
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50 moles of H2
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Calculate the percent composition of pentene. The formula for pentene is C5H10. 85.63% C, 14.37% H 75.24% C, 24.76% H 78.59% C, 21.41% H 81.75% C, 18.25% H
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85.63% C, 14.37% H
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What is the mass of 0.0600 moles of FeBr3? 8.15 grams 14.8 grams 17.7 grams 19.6 grams
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17.7 grams
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What is the mass of 2.50 moles of Al2O3? 102 amu 102 grams 255 amu 255 grams
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255 grams
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You have 6.02 x 1023 iron (Fe) atoms. How much does this collection of atoms weigh? 55.9 grams 27.9 grams 6.02 x 1023 grams 6.02 x 10-23 grams
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55.9 grams
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What is the molar mass of Ca(ClO4)2? 40.1 g/mol 71.0 g/mol 128.0 g/mol 239.1 g/mol
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239.1 g/mol
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Consider the following chemical reaction. C2H4 + 3 O2 ----> 2 CO2 + 2 H2O The O atoms in O2 are oxidized in this reaction. True False
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False
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What is the coefficient in front of the "C3H8" when the following chemical equation is balanced? CH4 ---> C3H8 + H2 1 2 3 4
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1
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Balance the following chemical equation. C2H2 + O2 ---> CO2 + H2O 2 C2H2 + 5 O2 ---> 4 CO2 + 2 H2O 1 C2H2 + 3 O2 ---> 2 CO2 + 3 H2O 2 C2H2 + 2 O2 ---> 2 CO2 + 4 H2O 3 C2H2 + 4 O2 ---> 3 CO2 + 6 H2O
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2 C2H2 + 5 O2 ---> 4 CO2 + 2 H2O
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A balanced equation has equal numbers of ________ on each side. reactants products bonds atoms
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atoms
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Find m, n, and l for the following reaction: m S8 + n O2 ---> l S2O3 m=1, n=6, l=4 m=2, n=4, l=8 m=3, n=18, l=12 m=4, n=8, l=16
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m=1, n=6, l=4
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Aluminum (Al) is oxidized in the chemical equation shown below: 4 Al + 3 O2 -----> 2 Al2O3 True False
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True
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What is the oxidation number of N in the N3- ion? 0 -3 +3 -9
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-3
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Balance the following chemical equation. CaH2 + H2O ---> Ca(OH)2 + H2 CaH2 + H2O ---> 2 Ca(OH)2 + 2 H2 CaH2 + 2 H2O ---> Ca(OH)2 + 2 H2 CaH2 + H2O ---> Ca(OH)2 + 2 H2 2 CaH2 + H2O ---> Ca(OH)2 + 2 H2
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CaH2 + 2 H2O ---> Ca(OH)2 + 2 H2
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Oxidation refers to the loss of electrons. True False
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True
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What is the oxidation number of C in CH4? +4 +2 -4 -2
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-4
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What is the coefficient in front of the "KCl" when the following chemical equation is balanced? KClO3 ---> KCl + O2 1 2 3 4
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2
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What is the coefficient in front of the "C3H8" when the following chemical equation is balanced? CH4 ---> C3H8 + H2 1 2 3 4
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1
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What is happening to the ethylene molecule (formula C2H4) in the reaction below? (pic of the below chemical equation) C2H4 + H2 ----> C2H6 The ethylene molecules is being hydrolyzed. The ethylene molecule is being oxidized. The ethylene molecule is being reduced. The ethylene molecule is undergoing combustion.
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The ethylene molecule is being reduced.
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The conversion of formic acid to formaldehyde is shown below. The formic acid is being reduced in this reaction. (pic of the below chemical equation) CO2H2 -----> COH2 Formic Acid Foraldehyde True False
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True
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The combustion of natural gas is an exothermic process. True False
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True
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The chemical reaction shown below is balanced: Cl2 + 2 KI -----> 2 K+ + 2 Cl- + I2 True False
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True
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What is the molar mass of (C2H5)2O? 28 g/mol 45 g/mol 74 g/mol 90 g/mol
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74 g/mol
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The reaction shown below is an example of a hydrolysis reaction: (pic of the below chemical equation) CONH3 + H2O -----> CO2H2 + NH3 True False
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True
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Determine the percent composition of Fe2O3. What is the percentage of iron in this compound? 40% 60% 70% 30%
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70%
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Calculate the percent composition of caffeine (C8H10N4O2). What is the percentage of nitrogen in caffeine? 28.9 % nitrogen 194 % nitrogen 56.0 % nitrogen 7.2 % nitrogen
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28.9 % nitrogen
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2.000 moles of NaCl corresponds to 29.225 grams of NaCl. True False
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False
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What is the correct formula mass for NH4OH? 34.02 amu 35.06 amu 45.64 amu 41.45 amu
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35.06 amu
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How many atoms are contained in a sample of krypton, Kr, that has a mass of 8.38 grams? 6.02 x 1023 6.02 x 1022 1 0.1
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6.02 x 1022
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How many atoms are in one mole? 6.02 x 1023 atoms 6.02 x 10-23 atoms It depends on the identity of the atom
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6.02 x 1023 atoms
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What is the mass of 0.300 moles of KCl? 22.4 amu 22.4 grams 74.5 amu 74.5 grams
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22.4 grams
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You have 6.02 x 1023 iron (Fe) atoms. How much does this collection of atoms weigh? 55.9 grams 27.9 grams 6.02 x 1023 grams 6.02 x 10-23 grams
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55.9 grams
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How many atoms are in 2.4 grams of magnesium? 6.0 x 1022 3.7 x 1022 2.5 x 1022 1.7 x 1022
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6.0 x 1022
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Calculate the number of grams in 2.50 moles of silver (Ag). 225.75 g 169.8 g 249 g 270. g
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270. g
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What is the mass of 0.0600 moles of FeBr3? 8.15 grams 14.8 grams 17.7 grams 19.6 grams
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17.7 grams
