Question

CHM 1210 Practice Problems 1210 Practice Problems on Solution Stoichiometry and Net Ionic Equations cinc reacts with acids to produce H, gas. If you have 100 g of Zn metal, what volume of 2.50 M HCl is needed to convert the Zn metal completely to Znions? Ans. 0.122L 2. A solution contains 15 R of Feci, in 500 mL of solution. What is the molarity of the solution? Ans. 0.18 M 5. What is the molarity of 25.0 mL of an H.SO, solution that requires 29.3 mL of 0.250 M NaOH to neutralize it? Ans. 0.147 M H2SO4 4. You have 200 ml of a 0.5 M NaCl solution. If you add water to bring the final volume to 500 ml, what is the new molarity of the solution? Ans. 0.2 M 5. 76.80 grams of apple juice (malic acid) requires 34.56 ml of 0.664 M NaOH to reach the endpoint in a titration. What is the (w/w) % of malic acid in this sample? Use the following equation to help you calculate the correct answer. Reaction: C.H.Os(aq) + 2NaOH(aq) -> Na,C.H.Os(aq) + 2 H2011 Ans. 2.01% 6. How many grams of O, are needed to burn completely 81 g of Al in the following reaction: 4 Al + 0, 2A1,03 Ans. 728 7. Write the molecular, complete ionic, and net ionic equation for each of the following reactions. a. K,SO() + 2AgNO3(aq) →? b. Na,CO, (aq) + 2HCl(aq) → ? c. Ni(NO Ilog) + Mg(OH)2(aq) → ? d. LiPO (69) CaCl(aq) → ? 8. Use the pictures below to determine whether each solution is a strong or weak acid, and why? NO, 0 H, 00 H,0 + HE+ CHO, HO HORO+60

Answer 1

② The balanced chemical equation of the reaction of zinc with tice is Zn + 2tice Znce & the Thus I mole of zinc metal (zn) reacts with 2 mole ce to produce I mole of zuce, and mole of the To determine number of me We can calculate number of mass by using the formula:

Number of moles = Mass Molar Mass zn - 10.og Molar Mass of Zn = 65.38 g/mol Given mass So wing we get No. of moles of Zna 100g g/mol 0153 moles 69:38

سرجیول Since Molarity = No. of moles of solute o volume of solution in so for tice we have - 2.som = No. of moles of tice - Volume $ tee solution from balanced chemical equation we know that I mole of Zn reacts with 2 moles of tice. so 0.153 moles of Zn will react with - 2x0.153 = 0.306 moles of tice. (int)

Thus OS If 10.0g of zu reacte completely it will yield Zuce which dissociates i solution to give Zn²+ and ce- ions. So 10.0g or 0.153 moles) of zu will - convent completely to zu²+ ions if it reacts with exactly 0.306 moles of tice. the required = 0.306 - moles Substituting it in , we get - 2.50 m = 0.306 mol - Volume (in ) This Volume = 0.306 mot (Because - 2.50 mot L M = mol/L is the unit 10.122LL of malarity? Thus 0.122 L of 2.som to convert 10.0g of on Zn²+ ions. tice is needed completely to

② By using to in using and used formulas 10, we can calculate Polarity of fell solution. first we calculate number of moles of fell in isg Molar Mass of fece = 162.2 g/mol Given Mass of rece sisg So using for la ☺ we have No. of moles of rece = mass of fece Molar Mars of felles --- 158 162.2 g/mol = 0.0923 moles Given volume of solution - seet 1000 - 20:56 (Because I = 1000 ml so ImL = - 1000 This 500 mL = soo x L = 5oo y ___1000 1000 2 using formula ② we have Molarity of No. of males of fece Fech solution solution in 0.0925 mol = 0.18 molly Vole 0.5L or 0.18M]