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Reactions of Main Group Elements with Hydrogen

  • Page ID
    604
  • periodic table.jpg
    Figure 2: Possible compounds hydrogen is capable of creating with the main group elements.

    Hydrogen Reactions

    Hydrides are binary compounds of hydrogen. There are three possible hydrides that can be formed: ionic hydrides, covalent hydrides, and metallic hydrides. Metallic hydrides form when hydrogen reacts with transition metals, therefore they will not be introduced in this module.

    Hydrogen and the S-Block

    Ionic hydrides form when hydrogen reacts with s-block metals, not including Be and Mg. These s-block elements are found in Group 1 and Group 2 of the periodic table and are the most active metals. Group 1 metals are referred to as alkali metals and have a charge of +1 Group 2 metals are referred to as alkaline earth metals and have a charge of +2. Both Group 1 and Group 2 metals have low electronegativity values (less than 1.2).

    O solvent

    References

    1. Ebbing, Darrell D., and Steven D. Gammon. General Chemistry. 9th. Brooks/Cole, 2009. 440-442, 920-924, 949-952. Print.
    2. Henderson, W. Main Group Chemistry. Illustrated. 3. Royal Society of Chemistry, 2000. 20-31. Print.
    3. Thomas, Jens. Noble Gases. Marshall Cavendish Corporation, 2003. 5. Print.

    Problems

    1. Write the equation of the reaction between hydrogen and strontium.
    2. Write the equation of the reaction between hydrogen and phosphorus.
    3. Write the equation of the reaction between hydrogen and potassium.
    4. Write the equation of the reaction between hydrogen and bromine.
    5. Write 3 possible hydrocarbons that contains 3 carbons atoms.

    Answers

    1. Sr(s) + H2(s) SrH2(s)
    2. P2(g) + 3H2(g) 2PH3(g)
    3. 2K(s) + H2(g) 2KH(s)
    4. H2(g) +Br2(g) 2HBr(g)
    5. C3H8, C3H6, C3H4 ....answers may vary