How many nitrogren atoms are in a 3.75mg of Mg(NO3)2?

Question

aaronq · Answer

find how many moles you have, then find how many molecules.

Multiply the number of molecules by 2 because there are 2 N atoms in $Mg(NO_3)_\color{red}{2}$

anonymous · Answer

Make sure to convert from mg-grams first.

anonymous · Answer

So i just convert mg to grams then divide by molar mass and multiply by avogadros number? Then multiply by 2?

aaronq · Answer

correct

anonymous · Answer

Wouldnt that give me the number of how many atoms in total time two and not just nitrogen? Because they gave me the mass of the entire compound

aaronq · Answer

no, because when you multiply moles is in terms of the molecule. when you multiply times avogadros number, you find how many molecules (collections of Mg(NO3)2).

anonymous · Answer

so when you said to find how many moles you meant moles of nitrogen not moles of the entire molecule?

anonymous · Answer

by the way, isn't it a compound because magnesium is a metal?

aaronq · Answer

moles of the entire molecule

aaronq · Answer

very true. they're almost used interchangeably, but you're right.

anonymous · Answer

ah, I'm sorry, it took me a while to understand. I think i just fully understood what you just said, thank you so much!

aaronq · Answer

no problem !

goformit100 · Answer

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