Question

If the pressure on a gas is increased, then its volume will decrease because the gas molecules will be pushed closer together.

Did the data support the hypothesis (above)?

Answer 1

I don’t have your data here, so I can’t say directly. To decide whether the data support that hypothesis (the pressure increase causes volume decrease — Boyle’s law for a fixed mass at constant temperature), you can run these checks:

1. Visual check
- Plot volume (V) versus pressure (P). You should see a decreasing trend.
- Better: plot P versus 1/V (or V versus 1/P). Boyle’s law predicts a straight line for P vs 1/V with intercept ≈ 0.

2. Numeric checks
- Compute the product P·V for each measurement. If Boyle’s law holds (isothermal, ideal conditions), P·V should be approximately constant across points. Report the mean and the standard deviation or coefficient of variation (std/mean). Small variation (within your experimental error) supports the hypothesis.
- Compute the Pearson correlation between P and V. A strong negative correlation (near −1) is expected.
- Fit a linear regression P = k*(1/V) + c. Check that c is near 0, k is positive, and R² is high. Also check the p-value for the slope to ensure it’s significantly different from zero.

3. Consider experimental conditions and limitations
- Temperature must be constant (isothermal). If T changed, P·V won’t be constant.
- At high pressures or with real gases, non-ideal behavior can cause deviations.
- Measurement error, leaks, or timing issues can also produce discrepancies.

If you paste your data (P and V pairs), I can run these calculations and tell you whether the data support the hypothesis and by how strongly.