Ask Question
4 April, 03:09

3) Lithium metal (Li) react with hydrosulfuric acid (HS) to produce hydrogen gas and magnesium chloride (Li 2 S). How many grams of Lithium metal are required to react completely with excess acid to produce 4.5 L of Hydrogen at 315K and 1.258 atm? Remember to balance the equation.

+1
Answers (1)
  1. 4 April, 06:33
    0
    3.066g

    Explanation:

    Step 1:

    The balanced equation for the reaction. This is given below:

    2Li + H2S - > Li2S + H2

    Step 2:

    Data obtained from the question.

    Volume (V) of H2 = 4.5L

    Temperature (T) = 315K

    Pressure (P) = 1.258 atm

    Note:

    Gas constant (R) = 0.0821atm. L/Kmol

    Number of mole (n) of H2 = ... ?

    Step 3:

    Determination of the number of mole of H2 produced.

    This can be obtained by using the ideal gas equation as follow

    PV = nRT

    Divide both side by RT

    n = PV / RT

    n = 1.258 x 4.5 / 0.0821 x 315

    n = 0.219 mole

    Therefore, 0.219 mole of H2 is produced.

    Step 4:

    Determination of the number of mole of Li that will produce 0.219 mole of H2.

    This is shown below:

    2Li + H2S - > Li2S + H2

    From the balanced equation above,

    2 moles of Li reacted to produce 1 mole of H2.

    Therefore, Xmol of Li will react to produce 0.219 mole of H2 i. e

    Xmol of Li = 2 x 0.219

    Xmol of Li = 0.438 mole

    Step 5:

    Conversion of 0.438 mole of Li to grams.

    Number of mole of Li = 0.438 mole

    Molar Mass of Li = 7g/mol

    Mass = number of mole x molar Mass

    Mass of Li = 0.438 x 7

    Mass of Li = 3.066g

    Therefore, 3.066g if Li is needed for the reaction.
Know the Answer?
Not Sure About the Answer?
Find an answer to your question ✅ “3) Lithium metal (Li) react with hydrosulfuric acid (HS) to produce hydrogen gas and magnesium chloride (Li 2 S). How many grams of Lithium ...” in 📘 Chemistry if you're in doubt about the correctness of the answers or there's no answer, then try to use the smart search and find answers to the similar questions.
Search for Other Answers