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Hydrolyiss of an alkyl halide (RX) by di...

Hydrolyiss of an alkyl halide `(RX)` by dilute alkali `[OH]^(ɵ)` takes place ismultaneously by `SN^(2)` and `SN^(1)` pathways. A plot of `-(1)/([RX]) (d[R-X])/(dt)` vs `[OH]^(ɵ)` is a straight line of the slope equal to `2 xx 10^(3) mol^(-1) L h^(-1)` and intercept equal to `1 xx 10^(2) h^(-1)`. Calculate the initial rate `("mole" L^(-1) min^(-1))` of consumption of `RX` when the reaction is carried out taking `mol L^(-1)` of `RX` and `0.1 mol L^(-1)` of `[OH]^(ɵ)` ions.

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To solve the problem, we need to calculate the initial rate of consumption of the alkyl halide \( RX \) when the concentrations of \( RX \) and \( OH^- \) ions are given. The reaction proceeds via both \( SN^2 \) and \( SN^1 \) pathways. ### Step-by-Step Solution: 1. **Write the Rate Expressions**: - For the \( SN^2 \) pathway: \[ \text{Rate}_{SN^2} = k_2 [RX][OH^-] \] - For the \( SN^1 \) pathway: \[ \text{Rate}_{SN^1} = k_1 [RX] \] 2. **Combine the Rate Expressions**: The overall rate of consumption of \( RX \) can be expressed as: \[ -\frac{d[R-X]}{dt} = k_2 [RX][OH^-] + k_1 [RX] \] This can be factored as: \[ -\frac{d[R-X]}{dt} = [RX] \left( k_2 [OH^-] + k_1 \right) \] 3. **Divide by [RX]**: To express the rate in terms of \( \frac{1}{[RX]} \): \[ -\frac{1}{[RX]} \frac{d[R-X]}{dt} = k_2 [OH^-] + k_1 \] 4. **Identify the Slope and Intercept**: From the problem statement, we know: - Slope \( m = 2 \times 10^3 \, \text{mol}^{-1} \text{L} \text{h}^{-1} \) - Intercept \( c = 1 \times 10^2 \, \text{h}^{-1} \) Therefore, we can write: \[ -\frac{1}{[RX]} \frac{d[R-X]}{dt} = 2 \times 10^3 [OH^-] + 1 \times 10^2 \] 5. **Substitute the Known Concentrations**: Given: - \( [RX] = 1.0 \, \text{mol L}^{-1} \) - \( [OH^-] = 0.1 \, \text{mol L}^{-1} \) Substitute these values into the equation: \[ -\frac{1}{1.0} \frac{d[R-X]}{dt} = 2 \times 10^3 \times 0.1 + 1 \times 10^2 \] 6. **Calculate the Rate**: \[ -\frac{d[R-X]}{dt} = 2 \times 10^3 \times 0.1 + 1 \times 10^2 \] \[ -\frac{d[R-X]}{dt} = 200 + 100 = 300 \, \text{mol L}^{-1} \text{h}^{-1} \] 7. **Convert to Minutes**: Since the question asks for the rate in \( \text{mol L}^{-1} \text{min}^{-1} \): \[ -\frac{d[R-X]}{dt} = \frac{300 \, \text{mol L}^{-1} \text{h}^{-1}}{60 \, \text{min h}^{-1}} = 5 \, \text{mol L}^{-1} \text{min}^{-1} \] ### Final Answer: The initial rate of consumption of \( RX \) is \( 5 \, \text{mol L}^{-1} \text{min}^{-1} \).

To solve the problem, we need to calculate the initial rate of consumption of the alkyl halide \( RX \) when the concentrations of \( RX \) and \( OH^- \) ions are given. The reaction proceeds via both \( SN^2 \) and \( SN^1 \) pathways. ### Step-by-Step Solution: 1. **Write the Rate Expressions**: - For the \( SN^2 \) pathway: \[ \text{Rate}_{SN^2} = k_2 [RX][OH^-] ...
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