Australia's Science Forum

How much HCl and KMnO4 will I need to fill 1 gas jar? (as per p40 The Laboratory)

You want to fill in gas jar with chlorine? Why?
"This is toxic if breathed in, causing severe lung damage. It irritates
the eyes, skin and respiratory system. It may trigger an asthma
attack and the effects of exposure may be delayed for some hours.
For a 15-minute exposure, the concentration of the gas in the
atmosphere should not exceed 1.5 mg m-3"

Teacher wants it for students to observe colour.

Over the past 30 years as a Labbie, I have been required to make chlorine gas. I acted under instruction and supervision for the first couple of attempts (yes, it does produce irritating gas!). I've always used approx. 1.0g manganese dioxide in a flask and then enough conc. hydrochloric to cover. This may need to be gently warmed (in a fume cupboard), then sealed with a gas jar lid with paraffin. Seems to work well

Thanx BBB

easier way
1 milton tablet 5-10 mL of 2M HCl

Jazz wrote: ↑03 May 2017, 11:49 easier way
1 milton tablet 5-10 mL of 2M HCl

Does this produce enough to see that the gas is yellow?

I think Jazz has left this site. But give it a go and see.