Some of the gases used in industry are stored in pressurized steel cylinders.
The cylinder valves for flammable gases are manufactured with left-handed screw threads, whereas those for non-flammable gases have right-handed screw threads. Why is it an advantage to use different screw threads for different types of gases?
The table below gives chemical information about five gases. No information is given for biogas.
| Name of gas | oxygen | helium | carbon dioxide | krypton | methane | biogas |
|---|---|---|---|---|---|---|
| Formula of gas | O2\text{O}_2O2 | He\text{He}He | CO2\text{CO}_2CO2 | Kr\text{Kr}Kr | CH4\text{CH}_4CH4 | |
| Relative formula mass (MrM_rMr) | 32 | 4 | 44 | 84 | 16 |
Which two gases in the table are noble gases?
Which gas in the table makes up approximately 21% of dry air?
Why is it not possible to give a single chemical formula or a fixed relative formula mass for biogas in the table?
Carbon dioxide and propane (C3H8\text{C}_3\text{H}_8C3H8) both have a relative formula mass of 44. State one hazard of propane that makes it much more dangerous to handle than carbon dioxide.
State which one of the gases in the table is:
reacted with steam in the chemical industry to manufacture hydrogen gas.
used to fill meteorological balloons due to its extremely low density and non-flammable nature.
used as a filling gas in high-efficiency double-glazing window units to minimize thermal energy transfer.
