Question

Suppose you had 2.0158 grams of hydrogen (H2).

A. How many moles of hydrogen do you have?
B. How many moles of oxygen would react with this much hydrogen?
C. What mass of oxygen would you need for this reaction?
D. How many grams of water would you produce?

Answer 1

With 2.0158 grams of hydrogen, you have 1.000 moles. 0.500 moles of oxygen are needed, weighing 16.00 grams. After the reaction, you would produce 18.015 grams of water.

Step-by-step explanation:

To answer these questions, we must first understand the stoichiometry of the reaction between hydrogen (H2) and oxygen (O2) to form water (H2O). The balanced chemical equation for the reaction is:

2 H2(g) + O2(g) → 2 H2O(l)

A. The molar mass of H2 is approximately 2.016 grams per mole. To find the number of moles of hydrogen you have:

Moles of H2 = Mass of H2 / Molar Mass of H2 = 2.0158 g / 2.016 g/mol = 1.000 moles

B. The balanced equation shows that 2 moles of H2 react with 1 mole of O2. Therefore, the number of moles of oxygen that would react with 1.000 moles of hydrogen is:

Moles of O2 = (1.000 moles H2) (1 mole O2 / 2 moles H2) = 0.500 moles

C. The molar mass of O2 is approximately 32.00 grams per mole. To find the mass of oxygen needed:

Mass of O2 = Moles of O2 × Molar Mass of O2 = 0.500 moles × 32.00 g/mol = 16.00 grams

D. From the balanced equation, we can see that 2 moles of H2 would produce 2 moles of H2O. Since you start with 1.000 moles of H2, you would produce 1.000 moles of H2O. The molar mass of H2O is approximately 18.015 grams per mole, so:

Mass of H2O = Moles of H2O × Molar Mass of H2O = 1.000 moles × 18.015 g/mol = 18.015 grams