A 0.531 g sample of cobalt, Co, is added to 196 mL of 0.100 M H2SO4 to produce c

Question

A 0.531 g sample of cobalt, Co, is added to 196 mL of 0.100 M H2SO4 to produce cobal I) sulfate and hydrogen gas. Cols) + H,SO,(aq) Coso,(aq) + H2(g) What is the limiting reactant? O Co(s) O H2SO4(aq) A volume of 185 mL of hydrogen is collected over water. The water level in the collecting vessel is the same as the outside level. Atmospheric pressure is 101.325 kPa, the temperature is 25 °C, and the vapor pressure of water at 25 is 3.167 kPa What is the percent yield of hydrogen gas for this reaction? Number

Explanation / Answer

Moles of Co = mass/molecular weight

= (0.531 g) / (58.933 g/mol)

= 0.00901 mol

Moles of H2SO4 = molarity x volume

= 0.1 mol/L x 0.196 L

= 0.0196 mol

From the stoichiometry of the reaction

1 mol Co reacts with = 1 mol of H2SO4

0.00901 mol Co reacts with = 0.00901 mol of H2SO4

Limiting reactant = Co (s)

Option A is the correct answer

Volume of H2 collected V = 185 mL = 0.185 L

Absolute pressure P = atmospheric - vapor pressure

= 101.325 - 3.167

= 98.158 kPa x 1 atm/101.325 kPa

= 0.9687 atm

Moles of H2 = PV/RT

= 0.9687 x 0.185 / 0.0821 x 298

= 0.007325 mol

Actual yield of H2 = 0.007325 mol

Theoretical yield of H2

= 0.00901 mol Co x 1 mol H2/1 mol Co

= 0.00901 mol

% yield = actual yield x 100 / theoretical yield

= 0.007325 x 100/0.00901

= 81.298%

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.