Chemical Equations and Stoichiometry: How to Calculate Moles
What is stoichiometry and how is it used in chemical equations?
Stoichiometry is a branch of chemistry that deals with the quantitative relationships between reactants and products in chemical reactions. It allows us to determine the amount of reactants needed and products formed in a chemical reaction based on the balanced chemical equation.
Given the chemical equation:
2 Na₂S₂O₃ + 4 HCl → 2 NaCl + 3 S + 2 SO₂ + 2 H₂O
If 25.2 moles of Na₂S₂O₃ are reacted with excess HCl, how many moles of NaCl can be formed?
Answer:
To find out the number of moles of NaCl formed, we need to use the stoichiometry concept and the balanced chemical equation provided.
In the balanced chemical equation 2 Na₂S₂O₃ + 4 HCl → 2 NaCl + 3 S + 2 SO₂ + 2 H₂O, the ratio of Na₂S₂O₃ to NaCl is 2:2. This means that for every 2 moles of Na₂S₂O₃, 2 moles of NaCl are formed.
Given that we have 25.2 moles of Na₂S₂O₃, using the ratio from the balanced equation, we can calculate the moles of NaCl formed:
25.2 moles Na₂S₂O₃ x (2 moles NaCl / 2 moles Na₂S₂O₃) = 25.2 moles NaCl
Therefore, 25.2 moles of NaCl can be formed when 25.2 moles of Na₂S₂O₃ react with excess HCl.