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3.9.5: Lecture Demonstration- Carbide Cannon

  • Page ID
    50737
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    Enthalpy of reactions:

    Assuming you want about a 1 kJ explosion, how much CaC2 would you add to a carbide cannon?

    (1) 2 C2H2 + 5 O2 → 4 CO2 + 5 H2O ΔH ?

    given

    (2) C + O2 → CO2 ΔHf = -393.5 kJ/mol

    (3) H2 + 1/2 O2 → H2O (g) Δ Hf = -241.82 kJ/mol

    (4) 2 C + H2 → C2H2(g) ΔHf = +226.7

    Calculated enthalpy change for combustion of 2 mol of acetylene, ΔH = -2511 kJ

    This is 48.2 kJ/g

    for 1 kJ, we need 1 kJ/48.2 kJ/g = 0.02 g of acetylene 

    CaC2 + 2 H2O → HCCH + Ca(OH)

    this requires 0.0008 mol of CaC2, which is 0.05 g. 

    Do it with a Bangsite Cannon! 


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