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GCSE Chemistry help?

Maybe this might seem a bit stupid lmao, but why is Mg + O^2 = MgO? I know you are yet to balance the equation, but why does oxygen not come as a pair anymore?
Thank you for any answers <3 this has honestly confused me for a while, apparently it's under the conservation of mass topic, but I dont really get that either xD
Reply 1
I’m pretty sure it’s because it will become 2MgO as the reactants will be 2 Mg + O2
Original post by lostwooloo
Maybe this might seem a bit stupid lmao, but why is Mg + O^2 = MgO? I know you are yet to balance the equation, but why does oxygen not come as a pair anymore?
Thank you for any answers <3 this has honestly confused me for a while, apparently it's under the conservation of mass topic, but I dont really get that either xD

Because two magnesium atoms reacts with the oxygen molecule:

2 Mg + O2 -> 2 MgO

And you have two rates of magnesium and oxygen on both sides of equation.

Explanation: When magnesium meets oxygen, the covalent bond of the oxygen molecule splits and two magnesium and oxygen ions occur and react with each other because of different charges (magnesium ions are positive, oxygen ions negative charged). That is the complete reaction:

2 Mg + O2 -> 2 Mg(+2) + 2 O(-2) -> 2MgO
(edited 2 months ago)
Reply 3
Original post by lostwooloo
oh! so when Mg and Oxygen react, there's 2 Magnesiums and Oxygen as a pair (is there a reason why theres 2 magnesiums or does that not matter lmao?) BUT THANKSSSS IF THATS THE CASE!!


A simple reason is : Because there’s 2 Oxygens , 4 electrons are NEEDED altogether.

EACH magnesium can only GIVE 2 electrons - so you would therefore need 2 magnesium atoms. So 4 electrons can be transferred by the 2 Magnesium atoms to the 2 Oxygen atoms
Original post by iby08
A simple reason is : Because there’s 2 Oxygens , 4 electrons are NEEDED altogether.

EACH magnesium can only GIVE 2 electrons - so you would therefore need 2 magnesium atoms. So 4 electrons can be transferred by the 2 Magnesium atoms to the 2 Oxygen atoms


True, that is a redoxreaction. Thanks that you mentioned it, I have forgotten to do.

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