5. Mistakes to avoid

5.1 Don't jump to conclusions

If I ask my machine to fill a syringe with 1 ml of water, but when the contents are weighed out, I only measure 9.5 g (ρ _water = 1), what should I conclude?

• Does my machine underfill?

• My scale underestimates?

• Did I lose water at the weigh-in?

• Has the water evaporated?

• Etc.

There are several possible causes. It is therefore important to :

• check the anomaly by carrying out another inspection (confirm or deny);

• ...