I'm bad at chemistry. Need help with a simple question. I tried finding other threads with chemistry but people that can help have either been offline for a long time or won't answer friend requests
Q: How many moles of hydrogen atoms are there in 6.4g of methane(CH4)?
A: 6.4g of CH4
1 mole of CH4 = 16g
6.4/16 = 0.4 moles
0.4 x 6x10^23 = 2.4x10^23 molecules of CH4
(as there are 5 atoms in 1 molecule we multiply by 5)
2.4x10^23 x 5 = 1.2x10^24 atoms
(4 fifths of atoms are hydrogens so...)
1.2x10^24 / 5 x 4 = 9.6x10^23 atoms of hydrogens
The question asked how many moles of hydrogens. Does this mean divide that final answer by 6x10^23? Or do we count 4 hydrogens as 1 molecule and divide by 4 again and then divide by 6x10^23?
Any help appreciated
I'm bad at chemistry. Need help with a simple question. I tried finding other threads with chemistry but people that can help have either been offline for a long time or won't answer friend requests
Q: How many moles of hydrogen atoms are there in 6.4g of methane(CH4)?
A: 6.4g of CH4
1 mole of CH4 = 16g
6.4/16 = 0.4 moles
0.4 x 6x10^23 = 2.4x10^23 molecules of CH4
(as there are 5 atoms in 1 molecule we multiply by 5)
2.4x10^23 x 5 = 1.2x10^24 atoms
(4 fifths of atoms are hydrogens so...)
1.2x10^24 / 5 x 4 = 9.6x10^23 atoms of hydrogens
The question asked how many moles of hydrogens. Does this mean divide that final answer by 6x10^23? Or do we count 4 hydrogens as 1 molecule and divide by 4 again and then divide by 6x10^23?
Any help appreciated
Are you sure the question asked specifically for hydrogen atoms? Because some asshole professors just call H2 hydrogen (gas).
Anyway, you basically answered your own question. You're just overthinking it. There are 0.4 mols of CH4, and each CH4 molecule has 4 mols of hydrogen atoms in them, so your answer comes out to be 1.6 mols of H.
Edit: Sorry, meant to say each mol of CH4 has 4 mols of H.
Are you sure the question asked specifically for hydrogen atoms? Because some asshole professors just call H2 hydrogen (gas).
Anyway, you basically answered your own question. You're just overthinking it. There are 0.4 mols of CH4, and each CH4 molecule has 4 mols of hydrogen atoms in them, so your answer comes out to be 1.6 mols of H.
Edit: Sorry, meant to say each mol of CH4 has 4 mols of H.
This part isn't wrong but it is unnecessary.
0.4 x 6x10^23 = 2.4x10^23 molecules of CH4
(as there are 5 atoms in 1 molecule we multiply by 5)
2.4x10^23 x 5 = 1.2x10^24 atoms
(4 fifths of atoms are hydrogens so...)
1.2x10^24 / 5 x 4 = 9.6x10^23 atoms of hydrogens
The problem asks for moles of H (not atoms of H) and you already have an expression for moles of H in terms of moles of methane. So rather than (methane mass --> methane moles --> methane molecules --> H atoms --> H moles) you can do (methane mass --> methane moles --> H moles).
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1 mol methane = 4 moles Hydrogen
This part isn't wrong but it is unnecessary.
[quote]0.4 x 6x10^23 = 2.4x10^23 molecules of CH4
(as there are 5 atoms in 1 molecule we multiply by 5)
2.4x10^23 x 5 = 1.2x10^24 atoms
(4 fifths of atoms are hydrogens so...)
1.2x10^24 / 5 x 4 = 9.6x10^23 atoms of hydrogens[/quote]
The problem asks for moles of H (not atoms of H) and you already have an expression for moles of H in terms of moles of methane. So rather than (methane mass --> methane moles --> methane molecules --> H atoms --> H moles) you can do (methane mass --> methane moles --> H moles).
[spoiler]1 mol methane = 4 moles Hydrogen[/spoiler]
Ok, thanks guys. Most of this makes sense to me...
except from knowing you have 0.4 moles of CH4, how can you know that there is 4 moles of hydrogen in each CH4 molecule?
Ok, thanks guys. Most of this makes sense to me...
except from knowing you have 0.4 moles of CH4, how can you know that there is 4 moles of hydrogen in each CH4 molecule?
There aren't 4 moles of hydrogen in a CH4 molecule, but there is a ratio of of carbon to hydrogen in methane. For every carbon, you have 4 hydrogens. So, for 1 mol of carbon, you have 4 moles of hydrogen in 1 mole of methane.
6.4g CH4 * 1mol CH4/16g CH4 * 4mol H/1mol CH4 = 1.6 mol H
There aren't 4 moles of hydrogen in a CH4 molecule, but there is a ratio of of carbon to hydrogen in methane. For every carbon, you have 4 hydrogens. So, for 1 mol of carbon, you have 4 moles of hydrogen in 1 mole of methane.
6.4g CH4 * 1mol CH4/16g CH4 * 4mol H/1mol CH4 = 1.6 mol H
This finally makes sense to me. Thanks to all you guys, you're awesome
This finally makes sense to me. Thanks to all you guys, you're awesome
wow a chemistry thread without Trekkie, i'm surprised
wow a chemistry thread without Trekkie, i'm surprised
Loronixwow a chemistry thread without Trekkie, i'm surprised
Yeah. Probably the only reason for that is because I got my answer before he got online XD
[quote=Loronix]wow a chemistry thread without Trekkie, i'm surprised[/quote]
Yeah. Probably the only reason for that is because I got my answer before he got online XD