點解氫係陽離子唔係陰離子?

Hydrogen can form hydorgen ion or hydride ion by losing one electron or gain one electron respectively. Whether it gain or lose electron, it mainly depends on the electronegativity of the element reacting with hydrogen. If the element reacting with hydrogen has a high electronegativity than hydrogen, it will take away the electron from hydrogen and hydrogen ion is form. One of the typical example is reaction between chlorine and hydrogen. Hydrogen ion and chloride ion is formed as the following equation:
H2+ Cl2 ----> 2H+ + 2Cl-

If the hydrogenreact with the element which has lower eletronegativity than hydrogen, the hydrogen will gain the lectron from this element and hydride ion will be formed. One of the typical example is the formation of sodium hydride.
H2 + 2Na -----> 2NaH ----> Na + + H-

However, this hydride ion is not very stable it will easily react with any proton source to form H2 and decompose. Say, once it contacts with water it will be hydrolyzed and form hydrogen. H- + H2O -----> H2 + OH-

I hope the information can help you!

幾好丫??個條友做咩　vote 負面姐

氫最外層電子數為1
所以在化學反應中
難以得到電子
形成負價
通常會跟其他元素以共價鍵形式形成他合物

可能係電解時氫氣會係負極出現卦

Actually, hydrogen can be changed into either cation or anion.

Cation is called hydrogen ion(loses 1 electron) while anion is called hydride(gains 1 electron).

因為只有金屬先會放電子 非金屬唔會架