Hydrogen and oxygen combine in the ratio of 1:8 by mass to form water. What mass of oxygen gas would be required to react completely with 3 g of hydrogen gas?

Explanation

To solve the problem of how much oxygen gas is required to react completely with 3 grams of hydrogen gas, we will follow these steps:

### Step 1: Understand the mass ratio
We know from the problem that hydrogen and oxygen combine in the ratio of 1:8 by mass to form water. This means:
- 1 gram of hydrogen (H) reacts with 8 grams of oxygen (O).

### Step 2: Set up the proportion
Given that 1 gram of hydrogen reacts with 8 grams of oxygen, we can set up a proportion to find out how much oxygen is needed for 3 grams of hydrogen.
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