The ion-product constant of water at 40 is

CHEMISTRY · Multi-part · A Level · Chemistry · Acids and bases · Acids and bases

Problem

The ion-product constant of water at 40

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K_w = 2.92 \times 10^{\! -14}

. Assume the water contains no added acid or base. (a) Calculate the molar concentration of hydronium ions in neutral water at 40

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. Show all work. (b) Determine the pH of the neutral water sample at 40

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. (c) Compare the pH you obtained in part (b) with the pH of neutral water at 25

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. State whether the neutral pH has increased or decreased, and briefly explain why.