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Need help with these questions (1 Viewer)

carrotsss

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For question 2, the difference between HCl and HCN is that HCl is a strong acid, and HCN is a weak acid. This means that HCl dissociates (more or less) completely in water, which means that more hydronium ions are created - you would mention this equation:
HCl(aq) + H2O(l) -> Cl-(aq) + H3O+(aq)
Meanwhile, because HCN is a weak acid, it only partially dissociates in water, meaning that far less hydronium ions ions are created - you would do a similar equation except with a reversible arrow, mentioning that the equilibrium is far shifted to the left hand side, and because the hydronium concentration is much lower, the pH is much higher (pH=-log[H3O+])
 

carrotsss

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For the first question, I can’t give exact answers because you’ve cut off the previous part, but the steps to complete it are:
1. Find the concentration of H2SO4 in the diluted solution, given the wording of the question you’ve already found this
2. Multiply this by 0.015 (the volume of diluted solution) to find the number of moles of H2SO4
3. Double it due to the molar ratio to find the moles of KOH needed in the reaction to neutralise it (you seem to have figured this out already)
4. Divide the needed moles of KOH by the concentration (0.005) to find the number of litres of it needed
 

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