working out mass of a sample of gas from a given volume???

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  1. 0121ali10's Avatar
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    working out mass of a sample of gas from a given volume???
    Hi. A sample of N2 gas occupies 4.48L of volume. What is the mass of the gas in grams? Please help me with this question.N has an atomic mass of 14.
  2. lebron_23's Avatar
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    Re: working out mass of a sample of gas from a given volume???
    The mass of a substance = The number of moles x Formula Mass. Therefore.. According to Avogadro's Law, one mole of a substance occupies 24dm3 of volume. And we also know that one mole is equal to the Formula Mass of a substance. Therefore.. The number of moles in N2 is 2 moles (equal to 28g). Because you have 4.48L (24dm3 = 24000L), you can convert that into dm3 by dividing by 1000. The volume now equals 0.00448 dm3. All of this is irrelevant, however as all you do is times the number of moles (2) by the Formula Mass (28)
    I'm not too sure if this is actually correct, because i sat my chemistry exam a few days ago and then subsequently wiped my brain of anything to do with chemistry.. So i apologise if i'm wrong.. And if i am wrong, someone who actually HAS some chemistry knowledge, please correct me
  3. lebron_23's Avatar
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    Re: working out mass of a sample of gas from a given volume???
    (Original post by lebron_23)
    The mass of a substance = The number of moles x Formula Mass. Therefore.. According to Avogadro's Law, one mole of a substance occupies 24dm3 of volume. And we also know that one mole is equal to the Formula Mass of a substance. Therefore.. The number of moles in N2 is 2 moles (equal to 28g). Because you have 4.48L (24dm3 = 24000L), you can convert that into dm3 by dividing by 1000. The volume now equals 0.00448 dm3. All of this is irrelevant, however as all you do is times the number of moles (2) by the Formula Mass (28)
    I'm not too sure if this is actually correct, because i sat my chemistry exam a few days ago and then subsequently wiped my brain of anything to do with chemistry.. So i apologise if i'm wrong.. And if i am wrong, someone who actually HAS some chemistry knowledge, please correct me
    Actually, i think that was a whole load of crap to be honest with you.. So pay no heed to my blabbering
  4. DeathByBSOD's Avatar
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    Re: working out mass of a sample of gas from a given volume???
    (Original post by 0121ali10)
    Hi. A sample of N2 gas occupies 4.48L of volume. What is the mass of the gas in grams? Please help me with this question.N has an atomic mass of 14.
    Why is this in news....:confused:
  5. Martyn*'s Avatar
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    • Location: Wigan
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    Re: working out mass of a sample of gas from a given volume???
    Pointless disclosing academic or scientific information like this on here. People on this forum only recognise a limited set of words or concepts: Dailymail, racism, benefit scroungers, and paedophiles.
  6. clownfish's Avatar
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    Re: working out mass of a sample of gas from a given volume???
    (Original post by 0121ali10)
    Hi. A sample of N2 gas occupies 4.48L of volume. What is the mass of the gas in grams? Please help me with this question.N has an atomic mass of 14.
    moles = volume in dm3/24

    1L = 1dm3

    Then use mass = moles x Mr

    Where Mr = 14x2.
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