Question

Antacids, such as Alka-Seltzer, use the reaction of sodium bicarbonate with citric acid in water solution to produce a fizz as follows: 3NaHCO3 + C6H8O7 → 3CO2 + 3H2O + Na3C6H5O7 If 4.11 g of the citric acid (C6H8O7, MW = 192 g/mol) react with excess sodium bicarbonate (NaHCO3), how many grams of carbon dioxide (CO2, MW = 44 g/mol) are formed as the solution fizzes?

Answer 1

Answer:

2.8248 g

Explanation:

First, consider the balanced chemical equation:

$3NaHCO_{3} +C_{6}H_{8}O_{7} --->3CO_{2} +3H_{2}O +Na_{3}C_{6}H_{5}O_{7}$

Then we calculate the number of moles in 4.11 g of citric acid:

n(citric acid)=$\frac{4.11g}{192g/mol}=0.0214mol$

According to the balanced reaction, one mole of citric acid produces 3 moles of carbon dioxide. That's 3 times the number f moles of citric acid. So we will do the same with the available number of moles of citric acid.

so n(carbon dioxide) = 0.0214 mol*3=0.0642 mol

mass(carbon dioxide)= mass*molar mass=0.0642 mol* 44g/mol

                                                                   = 2.8248 g