Q&A for How to Measure Gas

To find the density of a gas, you divide its weight (or mass) by its volume.

Yes, you must consider the buoyant force when a gas-filled balloon is weighed in air, especially if the gas is lighter than air. While buoyancy is negligible for dense solids, it is significant or dominant for gas-filled balloons. Therefore, your comparison to weighing a solid in a liquid is accurate, as the same physical principles apply.

Whether you can use a different octane rating depends on your specific vehicle. Most manufacturers specify the recommended octane grade (e.g., 87, 91, 93) for their cars. Always refer to your car's manual or fuel cap and use the specified grade.

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