Grade 5 · Science
Track mass in a closed system practice
Account for all matter, including gas, when interpreting a stated closed-system mass measurement.
Opening your practice adventure…
Try a sample
An open cup and contents lose 4 g while water vapor escapes. Which observation explains why this is not a closed-system test?
- The cup was visible.
- The initial mass was recorded.
- The balance displayed grams.
- Matter crossed the cup's boundary.
See the answer & why
Matter crossed the cup's boundary.
Escaping vapor carries matter out of the measured system.
A little hint: Check the system boundary and include every material inside it before comparing masses.
A teaching tip
Check the system boundary and include every material inside it before comparing masses.