Question

The reaction between C7H6O3 and C4H6O3 is given by

2 C7H6O3 + C4H6O3 → 2 CgH8O4 + H₂O

a) How many grams of C4H6O3 are required to react completely with 125g of salicylate acid, C7H₂O3.
b) Calculate the mass in grams of aspirin, C,H₂O4 formed in the above reaction, that is, reaction (a).​

Answer 1

a.) 46.2 g C₄H₆O₃

b.) 163 g C₉H₈O₄

Step-by-step explanation:

To find the masses of C₄H₆O₃ and C₉H₈O₄, you need to (1) convert grams C₇H₆O₃ to moles (via the molar mass), then (2) convert moles C₇H₆O₃ to moles C₄H₆O₃ / C₉H₈O₄ (via the mole-to-mole ratios from equation coefficients), and then (3) convert moles C₄H₆O₃ / C₉H₈O₄ to grams (via the molar mass). The final answers should have 3 significant figures.

Molar Mass (C₄H₆O₃): 4(12.011 g/mol) + 6(1.008 g/mol) + 3(15.998 g/mol)

Molar Mass (C₄H₆O₃): 102.086 g/mol

Molar Mass (C₇H₆O₃): 7(12.011 g/mol) + 6(1.008 g/mol) + 3(15.998 g/mol)

Molar Mass (C₇H₆O₃): 138.119 g/mol

Molar Mass (C₉H₈O₄): 9(12.011 g/mol) + 8(1.008 g/mol) + 4(15.998 g/mol)

Molar Mass (C₉H₈O₄): 180.155 g/mol

2 C₇H₆O₃ + 1 C₄H₆O₃ ------> 2 C₉H₈O₄ + H₂O
^ ^ ^

a.)

125 g C₇H₆O₃ 1 mole 1 mole C₄H₆O₃ 102.086 g
---------------------- x ---------------- x -------------------------- x ------------------ =
138.119 g 2 moles C₇H₆O₃ 1 mole

= 46.2 g C₄H₆O₃

b.)

125 g C₇H₆O₃ 1 mole 2 moles C₉H₈O₄ 180.155 g
---------------------- x ---------------- x -------------------------- x ------------------ =
138.119 g 2 moles C₇H₆O₃ 1 mole

= 163 g C₉H₈O₄