// Numbas version: finer_feedback_settings {"name": "calculating concentration of strong acid from pH", "extensions": ["chemistry"], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "calculating concentration of strong acid from pH", "tags": [], "metadata": {"description": "", "licence": "None specified"}, "statement": "

This question asks you to calculate the concentration of strong acids from their pH

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Remember that pH=-log[H+]. Remember that pH=-log[H+].  This can be arranged to give [H+]=$\\frac{10^{(-pH)}}{\\text{(no of protons on acid)}}$

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For a monoprotic acid (e.g. HCl) [HCl]= [H+], 

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for a diprotic acid (e.g. H2SO4) [H2SO4]=$\\frac{[H^{+}]}{2}$,

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for a triprotic acid (e.g. H3PO4) [H3PO4]=$\\frac{[H^{+}]}{3}$,

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This the concentration of the acid.

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A solution of {Acid_name} acid has a pH of {pH}.  Calculate its concentration in moldm-3.

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