Calculating Reactants in Chemical Reaction
How can we calculate grams of reactants in a chemical reaction?
In a reaction between sodium and chlorine gas, a student obtained 39.7 g of sodium chloride from 15.6 g of sodium. How many grams of chlorine gas reacted?
a. 24.09 grams
b. 34.62 grams
c. 45.78 grams
d. 51.25 grams
Answer:
24.09 grams of chlorine gas reacted.
Explanation:
A chemical equation for the reaction between sodium and chlorine is given as:
2Na(s) + Cl₂(g) → 2NaCl(s)
To calculate the grams of chlorine gas reacted, we need to follow these steps:
1. Determine the moles of sodium chloride formed:
Moles of NaCl = 39.7 g / 58.5 g/mol = 0.6786 mol
2. Use stoichiometry to find moles of chlorine gas:
According to the balanced equation, 2 moles of NaCl are formed from 1 mole of chlorine gas.
Therefore, 0.6786 moles of NaCl correspond to 0.3393 moles of chlorine gas.
3. Calculate the mass of chlorine gas:
Mass of 0.3393 moles of chlorine gas = 0.3393 mol × 71 g/mol = 24.09 g
Therefore, 24.09 grams of chlorine gas reacted in the given reaction.