A chemical reaction reduces the mass of a substance by 25% every hour. If the initial mass is 256 grams, how much remains after 4 hours?

Sun, 03 May 2026 09:05:14 +0000

**Why a Chemical Reaction Reduces Mass by 25% Every Hour—What This Means for Science and Everyday Life** In a quiet but growing conversation across science communities and everyday curiosity spaces, people are asking: *What happens when a substance loses 25% of its mass each hour? Is this more than a textbook example? Could this process really affect real-world materials?* The short answer involves a measurable decay pattern best understood through a steady, predictable chemical or physical decay—where mass diminishes progressively over time. If a substance begins at 256 grams and loses 25% of its current mass every hour, a curved but precise reduction unfolds. This type of transformation, often linked to environmental exposure, degradation processes, or specialized material science, holds relevance far beyond abstract theory—especially as digital curiosity shapes how we understand transformations in both nature and technology. The phenomenon described—losing 25% of initial mass per hour—correlates with a consistent exponential decay process. Mathematically, this means each hour, only 75% of the previous mass remains. Applying this over four hours creates a clear trajectory:
- After 1st hour: 256 × 0.75 = 192 grams
- After 2nd hour: 192 × 0.75 = 144 grams
- After 3rd hour: 144 × 0.75 = 108 grams
- After 4th hour: 108 × 0.75 = 81 grams Result: Just 81 grams remain after four full hours. This gradual loss is not unique to one chemical—similar patterns emerge in exposure to light, heat, or reactive environments—and explains why tracking mass decay is vital in fields ranging from archaeology to industrial quality control.