Question

6. At 150°C the decomposition of acetaldehyde CH3CHO to methane is a first order reaction. If the rate constant for the reaction at 150°C is 0.029 min-1 , how long does it take a concentration of 0.050 mol L-1 of acetaldehyde to reduce to a concentration of 0.040 mol L-1 ?

7. The decomposition of hydrogen iodide into hydrogen and iodine is a second order reaction. The rate constant k = 0.080 L mol-1 s-1 . How long does it take an initial concentration of 0.050 M to decrease to half this concentration?

8. The gold-198 isotope has a half-life of 2.7 days. If you start with 10 mg at the beginning of the week, how much remains at the end of the week, seven days later?

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