The correct one would be volume
Simple cations are formally called by their element names with a suffixed Roman numeral in parentheses to indicate its charge. A simple anion has a name that is the original elemental name with the final syllable changed to -ide.
Group 17 is the most readily reduced elements on the periodic table, meaning that they are so close to being a stable elements, only missing 1 electron to complete their valance electron shell. Thus they will essentially react with anything to get that last electron!
Group 1 elements are extremely reactive because they are the most readily oxidized, they are very close to reaching stability by giving up only 1 electron. Thus they will react with almost anything to give up their electron.
At constant temperature and pressure, increasing the amount of gas will increase the volume.
