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Homework Help: Chem Question

  1. Apr 13, 2005 #1
    Lets say you want to find the molar volume of a gas ([tex] H_{2} [/tex] specifically). So you basically use a [tex] Mg [/tex] ribbon and find the volume of the [tex] H_{2} [/tex] gas in a test tube with the [tex] Mg [/tex] ribbon. The water fizzes and bubbles. I am having trouble finding the volume of [tex] H_{2} [/tex] at STP. I used the formula: [tex] V_{1} = \frac{P_{1}}{T_{1}} \times \frac{T_{2}}{P_{2}} [/tex]. After plugging in experimental values I got 1.234. Does this make sense? What units is this in. To find the molar volume I know that I do the moles of H_2 gas divided by the volume of H_2 gas. Does it make sense to only have 0.0025 moles of H_{2} gas reacted? Because I se a Mg strip that was 1.20 grams.

    Any help is appreciated

    Last edited: Apr 13, 2005
  2. jcsd
  3. Apr 13, 2005 #2
    Is that the combined gas equation?

    [tex]\frac{p_{1} V_{1}}{T_{1}} = \frac{p_{2} V_{2}}{T_{2}} [/tex]

    Molar volume is the gas' volume divided by the moles of gas.
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