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 9.75 g 9.75 g 0.50 g 0.50 g 23.5 g 23.5 g 19.5 g 19.5 g

Answer 1

To find the answer, we first need to determine the molar mass of potassium oxide (K2O).

Molar mass of K2O = (2 x molar mass of K) + (1 x 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 number of moles of K2O in 23.5 grams:

23.5 g / 94 g/mol = 0.25 moles

Since the balanced equation shows that it takes 4 moles of K to produce 2 moles of K2O, we need half as many moles of K as we do K2O.

0.25 moles K2O x (4 moles K / 2 moles K2O) = 0.50 moles K

Finally, we can calculate how many grams of potassium (K) are needed to produce 0.50 moles:

0.50 moles x 39 g/mol = 19.5 g

Therefore, we need 19.5 grams of potassium to produce 23.5 grams of potassium oxide (K2O).
The answer is 19.5 g.