In the reaction 2H2 + O2 → 2H2O, how many grams of oxygen are required to comple

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Question: In the reaction 2H2 + O2 → 2H2O, how many grams of oxygen are required to completely react with 4 grams of hydrogen?

Options:

Correct Answer: 8 g

Solution:

4 g of H2 = 2 moles. 1 mole of O2 is needed for 2 moles of H2, so 1 mole of O2 = 32 g is required.

In the reaction 2H2 + O2 → 2H2O, how many grams of oxygen are required to completely react with 4 grams of hydrogen?

In the reaction 2H2 + O2 → 2H2O, how many grams of oxygen are required to completely react with 4 grams of hydrogen?

Step 1: Determine the molar mass of hydrogen (H2). The molar mass of H is approximately 1 g/mol, so H2 is 2 g/mol.
Step 2: Calculate how many moles of hydrogen are in 4 grams. Use the formula: moles = mass / molar mass. So, moles of H2 = 4 g / 2 g/mol = 2 moles.
Step 3: Look at the balanced chemical equation: 2H2 + O2 → 2H2O. This tells us that 2 moles of H2 react with 1 mole of O2.
Step 4: Since we have 2 moles of H2, we need half that amount of O2. Therefore, we need 1 mole of O2.
Step 5: Find the molar mass of O2. The molar mass of O is approximately 16 g/mol, so O2 is 32 g/mol.
Step 6: Calculate the mass of O2 needed. Since we need 1 mole of O2, the mass required is 1 mole × 32 g/mol = 32 grams.

Stoichiometry – The calculation of reactants and products in chemical reactions based on balanced equations.
Mole Concept – Understanding the relationship between grams, moles, and the molar mass of substances.