2 grams of potassium (K) reacts with 5 grams of Oxygen (O). According to the Law of Conservation of Mass, how many grams of potassium oxide (K2O) will be produced? (1 point) Responses 5 grams 5 grams 10 grams 10 grams 2 grams 2 grams 7 grams
The molar mass of potassium is about 39.1 g/mol, and the molar mass of oxygen is about 16 g/mol.
The balanced chemical equation for the reaction is:
4K + O2 -> 2K2O
From the equation, we can see that 4 moles of potassium react with 1 mole of oxygen to produce 2 moles of potassium oxide.
To find the number of moles present in the given amounts, we use the formula:
moles = mass / molar mass
Number of moles of potassium = 2 g / 39.1 g/mol ≈ 0.051 mol
Number of moles of oxygen = 5 g / 16 g/mol ≈ 0.313 mol
From the stoichiometry of the balanced chemical equation, we know that 4 moles of potassium react with 1 mole of oxygen. Therefore, the limiting reactant is potassium. This means that all of the potassium will react, and the amount of potassium oxide produced will be based on the amount of potassium.
According to the balanced chemical equation, 4 moles of potassium produce 2 moles of potassium oxide. Therefore, 0.051 mol of potassium will produce (0.051 mol / 4 mol) * 2 mol = 0.051 mol * 0.5 = 0.026 mol of potassium oxide.
To find the mass of the potassium oxide produced, we use the formula:
mass = moles * molar mass
Mass of potassium oxide = 0.026 mol * (39.1 g/mol * 2) ≈ 2.04 g
Therefore, approximately 2.04 grams of potassium oxide will be produced. Answer: 2 grams