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Leaddioxide + Conc. Hydrochlaric acid = Leadchloride + Water + Chloride​

Answer» <html><body><p><strong>Answer:a) First, we write the chemical reaction and we <a href="https://interviewquestions.tuteehub.com/tag/calculate-412157" style="font-weight:bold;" target="_blank" title="Click to know more about CALCULATE">CALCULATE</a> the relative molecular mass (or</strong></p><p><strong>atomic mass if it's an element) of each <a href="https://interviewquestions.tuteehub.com/tag/substance-1231528" style="font-weight:bold;" target="_blank" title="Click to know more about SUBSTANCE">SUBSTANCE</a> in the reaction:</strong></p><p><strong>PbO2 + 4 HCl → PbCl2 + Cl2 + 2 H2O</strong></p><p><strong>PbO2 Mm = 1 · 207,2 + 2 · 16,0 = 239,2 u (</strong></p><p><strong>1</strong></p><p><strong>)</strong></p><p><strong>HCl Mm = 1 · 1,0 + 1 · 35,5 = 36,5 u</strong></p><p><strong>PbCl2 Mm= 1 · 207,2 + 2 · 35,5 = 278,2 u</strong></p><p><strong>Cl2 Mm= 2 · 35,5 = 71,0 u</strong></p><p><strong>H2O Mm= 1 · 1,0 + 2 · 16,0 = 18,0 u</strong></p><p><strong>Mm 239,2 36,5 278,2 71,0 18,0</strong></p><p><strong>PbO2 + 4 HCl → PbCl2 Cl2 2 H2O</strong></p><p><strong>b) Second, we calculate the amount of substance (n) with the given data in the statement.</strong></p><p><strong>n = 31,2 g PbO2 · 1 mol PbO2 / 239,2 g PbO2 = 0,130 moles PbO2</strong></p><p><strong>c) Third, we balance the chemical equation.</strong></p><p><strong>Chemical reaction: PbO2 + 4 HCl → PbCl2 + Cl2 + 2 H2O</strong></p><p><strong>Pb 1 1</strong></p><p><strong>Cl 2 2 4</strong></p><p><strong>H 4 1</strong></p><p><strong>O 2 2</strong></p><p><strong>The equation is already balanced.</strong></p><p><strong>PbO2 + 4 HCl → PbCl2 + Cl2 + 2 H2O</strong></p><p><strong>d) Then, we collect all the information:</strong></p><p><strong>Mm 239,2 36,5 278,2 71,0 18,0</strong></p><p><strong>Stoichiometry 1 mol 4 moles 1 mol 1 mol 2 moles</strong></p><p><strong>PbO2 + 4 HCl → PbCl2 Cl2 2 H2O</strong></p><p><strong>Amount of</strong></p><p><strong>substance</strong></p><p><strong>0,130</strong></p><p><strong>moles</strong></p><p><strong>x moles y moles z moles t moles</strong></p><p><strong>1 unified atomic mass unit, symbol (u)</strong></p><p><strong>e) Fourth, we calculate the amount of the substances (n) in the chemical reaction:</strong></p><p><strong>x moles HCl = 0,130 moles PbO2 · 4 mol HCl / 1 mol PbO2 = 0,520 moles HCl</strong></p><p><strong>y moles PbCl2 = 0,130 moles PbO2 · 1 mol PbCl2 / 1 mol PbO2 = 0,130 moles PbCl2</strong></p><p><strong>z moles Cl2 = 0,130 moles PbO2 · 1 mol Cl2 / 1 mol PbO2 = 0,130 moles Cl2</strong></p><p><strong>t moles H2O = 0,130 moles PbO2 · 2 moles H2O / 1 mol PbO2 = 0,260 moles H2O</strong></p><p><strong>f) We collect the information again:</strong></p><p><strong>Mm 239,2 36,5 278,2 71,0 18,0</strong></p><p><strong>Stoichiometry 1 mol 4 moles 1 mol 1 mol 2 moles</strong></p><p><strong>PbO2 + 4 HCl → PbCl2 Cl2 2 H2O</strong></p><p><strong>Amount of</strong></p><p><strong>substance</strong></p><p><strong>0,130</strong></p><p><strong>moles</strong></p><p><strong>0,520</strong></p><p><strong>moles</strong></p><p><strong>0,130</strong></p><p><strong>moles</strong></p><p><strong>0,130</strong></p><p><strong>moles</strong></p><p><strong>0,260</strong></p><p><strong>moles</strong></p><p><strong>g) Then, we can answer the questions in the statement by <a href="https://interviewquestions.tuteehub.com/tag/using-7379753" style="font-weight:bold;" target="_blank" title="Click to know more about USING">USING</a> the amounts of substances:</strong></p><p><strong>What mass of lead dichloride would be obtained from 37,2 g of PbO2?</strong></p><p><strong>(step e) There will be produced 0,130 moles PbCl2</strong></p><p><strong>The mass is: 0,130 moles PbCl2 · 278,2 g PbCl2 /1 mol PbCl2 = 36,17 g PbCl2</strong></p><p><strong>What mass of <a href="https://interviewquestions.tuteehub.com/tag/chlorine-915874" style="font-weight:bold;" target="_blank" title="Click to know more about CHLORINE">CHLORINE</a> gas would be produced?</strong></p><p><strong>(step e) There will be produced 0,130 moles Cl2</strong></p><p><strong>The mass is: 0,130 moles Cl2 · 71,0 g Cl2 /1 mol Cl2 = 9,23 g Cl2</strong></p><p></p><p></p><p></p></body></html>


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