Moles question help/check?

Hiya, I’m a year 11 student currently doing some transition work for sixth form and have tried to complete the last question in my moles section for a while. I have tried my best but am very confused so a simple explanation would also be appreciated (simplified as much as you can haha).

Question: If I have 2.4g of magnesium, how many grams of oxygen are needed to completely react with the magnesium? Mg + O2 ——> MgO

My attempt:
So 2Mg + O2 —-> 2MgO

2.4g Mg x 2mol Mg/ 24.3gMg x 1mol O2/ 2mol Mg x 32/ 2mol Mg =
(cancelled the units)

2.4x1x32/24.3 x 2 x 2 = 12.64g

(That was my final answer although I can’t help but feel like I have gone wrong due to me being confused about the method {followed via a similar question on a YouTube video}).

Any help would be much appreciated!!!

Thanks :smile:

Reply 1

Matt978

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Not too sure where some of your numbers have come from. Does this make sense?

Reply 2

carxlinefxrbes_

Original post by Matt978

Not too sure where some of your numbers have come from. Does this make sense?

Yes this makes a lot more sense then the working out from the YouTube vids I was watching haha, I didn’t really know where half the numbers were coming from as well to be honest. Thank you for your help! :smile: