A Gas-Phase Decomposition Is First-Order with Respect to the Reactant

question 42

Multiple Choice

A gas-phase decomposition is first-order with respect to the reactant, R. If the initial concentration of R is 1.0 × 10⁻⁴ mol L⁻¹and the rate constant k = 1.08 × 10⁻⁶ s⁻¹, what concentration of R remains after 25 days?

• A)1.0 × 10 ⁻³ mol L ⁻¹
• B)1.0 × 10 ⁻⁴ mol L ⁻¹
• C)9.6 × 10 ⁻⁵ mol L ⁻¹
• D)4.3 × 10 ⁻⁵ mol L ⁻¹
• E)9.7 × 10 ⁻⁶ mol L ⁻¹

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