Use the chemical equation to answer the question. 4K(s) + O2(g) → 2K2O(s) The molar mass of potassium (K) is 39 g/mol. The molar mass of oxygen (O) is 16 g/mol. How many grams of potassium are needed in the reaction to produce 23.5 grams of potassium oxide (K2O)? (1 point) Responses 23.5 g 23.5 g 19.5 g 19.5 g 9.75 g 9.75 g 0.50 g
To solve this problem, we first need to calculate the molar mass of potassium oxide (K2O):
Molar mass of K2O = (2 x molar mass of K) + molar mass of O
Molar mass of K2O = (2 x 39 g/mol) + 16 g/mol
Molar mass of K2O = 78 g/mol + 16 g/mol
Molar mass of K2O = 94 g/mol
Now we can calculate the moles of K2O produced from 23.5 grams:
moles = mass / molar mass
moles = 23.5 g / 94 g/mol
moles = 0.25 mol
Since the balanced chemical equation shows that 4 moles of potassium are needed to produce 2 moles of K2O, we can calculate the moles of potassium needed:
moles of K = (4 moles of K / 2 moles of K2O) x moles of K2O
moles of K = (4 / 2) x 0.25 mol
moles of K = 0.5 mol
Finally, we can calculate the grams of potassium needed:
mass = moles x molar mass
mass = 0.5 mol x 39 g/mol
mass = 19.5 g
Therefore, 19.5 grams of potassium are needed in the reaction to produce 23.5 grams of potassium oxide (K2O). So the answer is 19.5 g.