Collecting a gas sim
Two questions choose the method: is the gas soluble in water, and is it denser or less dense than air (M_r about 29)?
Collecting a gas · covers the GCSE, IGCSE, O-Level topic
What the sim shows
Two questions choose the method: is the gas soluble in water, and is it denser or less dense than air (M_r about 29)? A gas denser than air goes by downward delivery into an upright jar; a lighter gas by upward delivery into an inverted one. A gas that is insoluble or only slightly soluble can go over water, and over water is the only choice when its density is close to air's, like oxygen. A soluble gas vanishes into the trough. Only over water can you read a volume: in air the gas mixes with the air it pushes out, so you get a jar of gas, not a measured volume. The gas flows at 3 cm³/s, and the clock runs 10 times faster than real time. The flask stands for whichever reaction makes the gas.
Use it in your lessons
- Try it here: anyone can unlock 2 figures free, and a free account unlocks up to 5. Runs on a laptop, a Chromebook or a phone; nothing to install.
- Present it and share student links with the teacher plan, from US$5 a month, billed yearly.
- Put it on your own website or LMS for US$9, paid once, or every sim from US$29 a month.
Free guide: 12 practicals as sims, and how to run one in a lesson →
Need a version for your exact set-up? Have one made: US$49 a figure in an order of 5.
More chemistry sims
- Collision theory simCaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂.
- Colour tests simEach tube holds 2.0 cm³ and each drop is 0.05 cm³.
- Cracking simCracking breaks long alkane molecules into shorter alkanes and alkenes.
- Diffusion in a liquid simOne crystal of potassium manganate(VII), 0.6 mg, goes into 150 cm³ of still water.
- Diffusion in a gas simAmmonia (Mᵣ 17) diffuses from the left, hydrogen chloride (Mᵣ 36.5) from the right.
- Disappearing cross simMake 50 cm³ of mixture from 0.20 mol/dm³ sodium thiosulfate and water, warm it to the temperature in a water bath, and stand the flask on the card.