How many grams of potassium carbonate?

Question

According to the following reaction, how many grams of potassium carbonate will be formed upon the complete reaction of 28.9 grams of potassium hydroxide with excess carbon dioxide?

CO2+2KOH=K2CO3+H2O

Answer 1

Hello, Nya,

CO₂+2KOH = K₂CO₃+H₂O

The equation is balanced, so we know that 2 moles of KOH will produce 1 moles of K₂CO₃, assuming 100% yield. Let's determine the number of moles in 28.9 grams of KOH by dividing by it's molar mass.

28.9 grams/(56.1 g/mole) = 0.51334 moles KOH. We'll only get half that many moles of K₂CO₃ , according to the equation. So we'll obtain 0.2567 moles of K₂CO₃ . Multiply by the molar mass of potassium carbonate to obtain grams:

(0.2567 moles)*(138.2 g/mole) = 35.48 grams K₂CO₃ That would be 35.5 grams K₂CO₃ with 3 sig figs

Bob